Analysis of the distribution of HII regions

4. NOTES ON INDIVIDUAL GALAXIES

In this section we give some comments on the deprojection angles chosen for each individual galaxy. This information is shown in Table 2. In Column 1 we give the galaxy name. In Columns 2 and 3 we show the PA and IA obtained using our two methods. In the first row we show the values for our first method, while in the second row those for our second method. If there are more than one catalog for a particular galaxy, the values found using our methods are displayed in the following lines. In Columns 4 and 5 we show the main values of PA and IA respectively found in the literature. In Column 6 we give a key to describe the method used to obtain the literature values. P is used for photometric values, KH is used for values determined using HI velocity field, KC for values determined using a velocity field in CO, KO for optical velocity fields, KS is used when the values come from slit spectra determinations and finally O is used for methods different to the previous ones. In Column 7 we give a key for the reference where this particular determination can be found. This key is resolved in Table 3. Finally in Columns 8 and 9 we give the adopted values of the PA and IA respectively. This same structure is repeated in the second group of columns. Using the finally adopted values we can deproject the catalogs of HII regions. The deprojected distribution of the richer catalogs showing with spiral structure are shown in Fig. 5 while in Fig. 6 we present the rest.


	Figure 5. Deprojected HII region distribution of the galaxies in our sample with rich catalogs and clear spiral structure.




Figure 6. Deprojected HII region distribution of the rest of the galaxies in our sample.

ESO 111-10: This is a galaxy with apparent small size and the catalog of HII regions is not very rich. Nevertheless, our two methods give a good agreement when we use a secondary minimum for the second method. We adopt the mean of both methods, which agrees well with RC3.

**Table 2.** Deprojection angles of the galaxies of the new sample. See the text for a full description.
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
ESO 111-10	60	55					55	55
	50	55
			50	52	P	3
			50	50	P	101
			115	52	P	106
ESO 152-26	10	45					20	47
	10	50
			29	45	P	3
			29	46	P	101
			20	49	P	106
ESO 377-24	115	40					100	35
	100	35
			101	32	P	3
			101	34	P	101
IC 1438	165	45					145	45
	145	45
			-	32	P	3
			-	22	P	101
			145	26	P	106
IC 2510	155	60					152	60
	150	60
			148	58	P	3
			148	58	P	101
IC 2560	40	55					42	57
	45	60
			45	51	P	3
			45	41	P	101
IC 3639	100	35					105	20
	105	20
			-	18	P	3
			100	37	P	38
			72	26	P	39
			81	22	P	39
			-	0	P	101
IC 4754	70	30					90	25
	90	25
			90	27	P	3
			90	26	P	101
			115	27	P	106
IC 5240	115	55					100	55
	100	55
			100	48	P	3
			100	53	P	101
			100	46	P	106
NGC 0053	180	45					160	46
	170	45
			160	46	P	3
			160	47	P	101
			148	37	P	106

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 0157	35	50					35	50
	35	50
			35	45	P	1
			30	50	P	3
			40	42	O	15
			40	44	P	16
			30	58	KS	17
			36	48	KS	54
			40	45	KH	78
			32	46	P	99
			42	51	KH	125
NGC 0210	160	60					162	57
	165	55
			160	54	P	1
			165	49	P	3
			160	50	P	16
			159	46	P	106
NGC 0598	45	45					23	55
	45	45
			23	46	P	3
			23	58	O	10
			24	55	O	15
			23	55	P	117
			23	55	P	118
			22	54	KH	119
			22	54	KH	120
			35	50	O	121
			23	56	KH	122
			21	56	KH	124
NGC 1068	40	55					84	29
	30	60
			106	32	P	1
			70	32	P	3
			10	45	P	38
			113	27	P	39
			175	36	P	39
			31	21	O	60
			82	37	KC	77
			70	25	P	83
			87	40	KC	88
			84	40	KC	89
			77	39	KS	91
			19	38	P	105
			90	-	KO	109
			80	19	KO	112
			74	22	KO	113
			90	20	KO	114
			106	40	O	116

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 1097	110	50					130	50
	130	50
			127	50	P	1
			130	47	P	3
			-	50	P	20
			131	37	O	60
			134	46	KH	86
			115	48	P	90
			130	52	P	101
NGC 1386	30	65					30	65
	30	65
			25	68	P	3
			25	68	P	101
NGC 1433	100	45					21	33
	115	50
			-	24	P	3
			17	27	P	58
			21	33	KH	76
			-	0	P	101
NGC 1566	50	40					41	32
	10	30
			50	30	P	2
			60	37	P	3
			41	27	KO	4
			41	32	P	4
			47	28	O	15
			47	36	KH	56
			21	36	P	58
			21	30	P	59
			12	47	O	79
			20	30	P	80
			30	48	O	98
			90	46	P	101
NGC 1667	140	55					147	50
	155	45
			-	39	P	3
			0	66	P	38
NGC 1672	170	45					170	34
	-	-
			170	34	P	3
			152	36	P	58
			170	27	P	101
NGC 1808	145	65					128	48
	150	75
			133	53	P	3
			142	67	KS	18
			-	62	P	20
			128	48	KH	96
			133	46	P	101

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 1832	20	45					20	42
	20	40
			0	41	P	1
			-	49	P	3
			16	44	O	15
			10	47	P	16
			17	60	KS	87
			1	46	P	106
NGC 2985	180	35					180	36
	-	-
			165	36	P	1
			180	37	P	3
			182	37	P	63
NGC 2997	115	35					100	40
	85	45
			92	46	P	1
			110	41	P	3
			110	40	KO	5
			99	45	O	15
			-	36	P	20
			93	32	O	60
			90	31	O	98
			-	22	P	101
NGC 3081	75	50					91	39
	65	75
(2nd cat.)	50	50
(2nd cat.)	65	65
			158	39	P	3
			85	34	P	75
			97	44	KO	75
			75	56	P	83
			158	32	P	101
			89	32	P	106
NGC 3198	45	65					36	71
	40	70
			35	67	P	3
			36	72	KH	7
			38	70	O	10
			36	72	KO	19
			-	68	P	20
			36	70	KH	21
			36	70	P	22
			42	73	O	60
			35	71	KO	74
			-	73	P	108

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 3359	185	65					171	52
	195	60
			172	60	P	1
			170	53	P	3
			-	53	P	20
			175	57	KS	81
			170	53	KO	85
			172	51	KH	94
			172	51	KH	95
NGC 3367	115	40					100	40
	85	40
			109	6	P	1
			-	29	P	3
			-	18	O	23
			71	37	O	60
NGC 3393	80	30					80	27
	80	25
			-	24	P	3
			41	30	P	39
			160	75	P	83
			-	0	P	101
NGC 3631	110	25					150	22
	120	20
			126	32	P	1
			-	17	P	3
			124	28	O	15
			-	25	P	20
			150	-	KH	97
			134	24	O	98
			-	22	O	102
NGC 3660	120	40					120	37
	120	35
			96	28	P	1
			110	36	P	3
NGC 3783	140	30					137	30
	135	30
			-	27	P	3
			134	22	P	39
			-	19	P	101
NGC 3982	0	10					7	21
	0	15
			6	14	P	1
			-	29	P	3
			17	27	P	105
			13	31	P	115

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 4051	65	40					132	40
	90	30
			96	43	P	1
			135	42	P	3
			125	69	P	38
			132	40	KH	73
			143	61	P	92
			130	37	KO	93
			135	63	P	115
NGC 4123	-	-					141	42
	145	35
			117	42	P	1
			135	42	P	3
			135	40	KH	65
			147	45	KH	104
NGC 4258	155	75					157	72
	160	70
			150	67	P	3
			150	72	P	22
			157	64	KS	24
			146	72	KS	25
			155	64	KS	26
			152	72	KH	27
			150	72	KH	28
			157	64	O	60
			159	63	P	63
			-	71	O	102
			162	56	P	105
NGC 4321	100	30					153	32
	100	35
			58	25	P	1
			30	32	P	3
			153	27	KH	6
			146	28	O	15
			-	21	P	20
			158	31	KO	37
			117	35	KS	36
			-	31	O	60
			153	27	P	64
			-	30	O	102
			153	-	KH	110
NGC 4507	65	55					60	33
	55	45
			-	37	P	3
			60	33	P	39
			-	19	P	101

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 4593	80	50					80	44
	85	50
(2nd cat.)	60	50
(2nd cat.)	-	-
(3rd cat.)	75	30
(3rd cat.)	80	45
			89	47	P	1
			-	42	P	3
			108	45	P	39
			80	56	P	38
			97	9	O	60
NGC 4602	100	65					96	65
	95	70
(2nd cat.)	95	60
(2nd cat.)	95	65
			105	70	P	3
			81	73	P	16
			97	69	O	60
NGC 4639	130	55					127	55
	125	55
			120	52	P	1
			123	47	P	3
			-	52	O	102
NGC 4699	50	50					47	47
	45	45
			41	41	P	1
			45	46	P	3
			48	43	O	60
NGC 4736	115	40					118	37
	120	25
(2nd cat.)	130	40
(2nd cat.)	90	40
			92	37	P	1
			105	36	P	3
			89	40	P	8
			123	35	KS	29
			114	36	KS	30
			113	40	KS	31
			115	35	KO	32
			103	36	KS	33
			122	36	KS	33
			118	35	KH	34
			128	35	O	60
			120	40	KH	71
			115	35	KC	72

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 4939	30	55					19	56
	10	60
(2nd cat.)	20	60
(2nd cat.)	15	60
			10	59	P	3
			8	61	O	15
NGC 4995	100	50					100	50
	100	50
			92	45	P	1
			95	49	P	3
NGC 5033	170	55					171	62
	175	60
			170	62	P	3
			-	62	P	20
			173	63	KH	21
			172	62	P	22
			170	63	P	38
			167	58	O	60
			173	60	P	63
			167	67	KH	100
			-	70	O	102
NGC 5194	20	35					170	20
	20	45
(sec.min.)	175	15
(sec.min.)	175	30
			27	37	P	1
			163	52	P	3
			37	33	P	8
			170	20	KO	9
			30	37	O	10
			-	53	P	20
			0	55	KO	40
			170	20	KO	41
			170	20	KH	42
			0	35	KS	43
			20	35	KH	44
			172	20	KH	45
			170	30	KH	46
			42	35	O	60
			36	35	P	84
			32	31	O	98
			143	26	P	105
NGC 5364	35	55					37	52
	40	50
			29	56	P	1
			30	50	P	3
			25	47	O	60
			43	52	P	92
			-	50	O	102

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 5371	45	50					7	39
	45	45
			5	51	P	1
			8	37	P	3
			-	36	P	20
			8	34	P	22
			-	34	KS	47
			-	57	O	102
NGC 5427	90	30					90	30
	65	40
(2nd cat.)	30	45
(2nd cat.)	45	40
(3rd cat.)	135	35
(3rd cat.)	90	25
			72	25	P	1
			-	32	P	3
			150	40	O	10
			68	32	P	48
NGC 5457	-	0					39	18
	155	0
(2nd cat.)	-	0
(2nd cat.)	125	5
			-	21	P	3
			39	18	KH	11
			35	27	KO	12
			38	24	O	15
			-	15	P	20
			-	20	KH	49
			-	18	KH	50
			-	20	KH	51
			-	0	O	60
			-	41	O	102
			35	-	KH	111
NGC 5643	70	30					70	30
	50	35
			-	29	P	3
			-	24	P	101
NGC 5861	160	60					152	56
	155	65
			149	56	P	1
			155	57	P	3
			150	56	P	16
			152	56	P	103

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 6070	70	65					65	60
	60	55
			56	60	P	1
			62	58	P	3
			64	61	O	60
NGC 6118	60	70					57	70
	55	70
			58	65	P	3
			58	70	P	16
			58	62	KS	52
NGC 6221	25	45					25	45
	-	-
			5	46	P	3
			28	45	P	70
			5	50	P	101
NGC 6300	115	60					108	52
	120	55
(2nd cat.)	130	55
(2nd cat.)	125	55
			118	49	P	3
			108	50	P	69
			108	52	KO	69
			108	52	KH	76
			118	48	P	101
			105	49	P	106
NGC 6384	40	45					40	47
	40	50
			31	50	P	1
			30	49	P	3
			33	49	P	92
			-	54	O	102
			33	37	P	105
NGC 6753	35	35					25	35
	15	35
			30	29	P	3
			30	27	P	101
			35	32	P	106
NGC 6764	55	60					55	60
	55	60
			62	62	P	1
			62	56	P	3
NGC 6782	50	40					42	37
	35	35
			45	49	P	3
			45	24	P	101
			35	27	P	106

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 6814	195	0					176	22
	165	35
(2nd cat. )	180	20
(2nd cat. )	175	20
			167	7	P	1
			-	21	P	3
			176	22	KH	73
			113	22	P	105
NGC 6902	160	55					157	50
	155	45
			153	46	P	3
			153	48	P	101
			131	37	P	106
NGC 6935	15	30					15	30
	-	-
			-	32	P	3
			-	0	P	101
			9	18	P	106
NGC 6937	-	-					15	30
	15	30
			-	27	P	3
			-	0	P	101
			28	39	P	106
NGC 6951	150	50					147	40
	145	30
			157	44	P	1
			170	34	P	3
			-	47	O	102
			-	40	P	20
NGC 7020	160	65					162	65
	165	65
			165	61	P	3
			165	65	P	101
			163	64	P	106
NGC 7098	70	60					73	52
	65	65
			74	50	P	3
			74	50	P	101
			71	55	P	106

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 7219	20	45					20	42
	20	40
			27	53	P	3
			27	54	P	101
			30	50	P	106
NGC 7267	130	40					3	26
	100	45
			6	34	P	3
			6	34	P	101
			3	26	P	106
NGC 7314	180	55					178	64
	185	65
(2nd cat.)	175	65
(2nd cat.)	175	70
			183	63	P	3
			-	65	P	20
			180	63	P	38
			180	70	O	60
			183	65	P	101
NGC 7329	120	50					120	50
	105	65
			107	47	P	3
			107	43	P	101
			112	46	P	106
NGC 7331	170	75					170	77
	170	80
			171	69	P	3
			168	75	KH	7
			171	74	P	8
			165	70	O	10
			167	74	O	15
			-	75	P	20
			168	77	KH	21
			165	69	KS	53
			170	70	KS	54
			165	69	O	60
			165	63	KC	61
			170	63	P	63
			167	75	KO	67
			170	67	P	68
			166	67	P	92
			-	73	P	102
			-	75	P	108

**Table 2.** Continued
Galaxy	1st & 2nd		Lit.		Type	Ref.	Adopted
Name	PA	IA	PA	IA			PA	IA
NGC 7479	60	45					22	51
	20	50
(2nd cat.)	40	50
(2nd cat.)	20	45
			39	45	P	1
			25	40	P	3
			37	45	P	14
			37	44	O	15
			22	51	KO	33
			39	42	P	57
			36	37	P	58
			36	36	O	60
			22	51	KH	62
			29	40	P	63
			40	40	P	64
			21	38	P	66
			15	45	KO	81
			16	45	KS	82
			-	55	P	102
			11	35	P	107
			40	40	P	124
NGC 7531	35	65					25	65
	25	65
			15	67	P	3
			14	65	P	55
			22	66	KO	55
			21	67	KH	56
			15	67	P	101
			20	63	P	106
NGC 7552	165	35					181	37
	160	30
			181	37	P	3
			181	27	P	101
NGC 7590	25	65					25	65
	25	65
			36	68	P	3
			25	60	P	38
			36	66	P	101

ESO 152-26: For this galaxy the HII regions are placed mainly in the arms and in the inner ring. Our two methods give the same value for the position angle and close values for the inclination angle. Eye estimates, however, show that the value of the PA is not satisfactory, presumably because our methods try to circularize the ring. We thus use the PA from the photometry of Crocker et al. (1996) and the mean of our IAs, which is also the mean of the literature values.

**Table 3.** Key for the references in Table 2

Key for the References
(1) Grosbøl ([1985])
(2) de Vaucouleurs ([1973])
(3) RC3 ([1991])
(4) Pence et al. ([1990])
(5) Milliard & Marcelin ([1981])
(6) Guhatakurta et al. ([1988])
(7) Begeman ([1987])
(8) Boroson ([1981])
(9) Tully ([1974])
(10) Considère & Athanassoula ([1988])
(11) Bosma et al. ([1981])
(12) Comte et al. ([1979])
(13) Begeman ([1989])
(14) Okamura ([1978])
(15) García-Gómez & Athanassoula ([1991])
(16) Mathewson & Ford ([1996])
(17) Burbidge et al. ([1961])
(18) Burbidge & Burbidge ([1968a])
(19) Bottema ([1988])
(20) Balkowski ([1973])
(21) Bosma ([1981])
(22) Wevers et al. ([1986])
(23) Dickson & Hodge([1981])
(24) Burbidge et al. ([1962])
(25) van der Kruit ([1974])
(26) Chincarini & Walker ([1967a])
(27) van Albada & Shane ([1975])
(28) van Albada ([1980])
(29) Burbidge & Burbidge ([1962])
(30) van der Kruit ([1976])
(31) Chincarini & Walker ([1967b])
(32) Buta ([1988])
(33) Pellet & Simien ([1982])
(34) Bosma et al. ([1977])
(35) Rubin et al. ([1964])
(36) van der Kruit ([1973])
(37) Arsenault et al. ([1988])
(38) Hunt et al. ([1999])
(39) Schmitt & Kinney ([2000])
(40) Carranza et al. ([1969])

**Table 3.** Continued

Key for the References

(41) Goad et al. ([1979])
(42) Rots et al. ([1990])
(43) Burbidge & Burbidge ([1964])
(44) Roberts & Warren ([1970])
(45) Weliachew & Gottesman ([1973])
(46) Shane ([1975])
(47) Zasov et al. ([1987])
(48) Blackman ([1982])
(49) Huchtmeier ([1975])
(50) van der Hulst & Sancisi ([1988])
(51) Huchtmeier & Witzel ([1979])
(52) Meyssonier ([1984])
(53) Rubin et al. ([1965])
(54) Afanasiev et al. ([1989])
(55) Buta ([1987a])
(56) Becker et al.([1988])
(57) Lu ([1998])
(58) Baumgart & Peterson ([1986])
(59) Hackwell & Schweizer ([1983])
(60) Danver ([1942])
(61) von Linden et al. ([1996])
(62) Laine & Gottesman ([1998])
(63) Héraudeau & Simien ([1996])
(64) de Jong & van der Kruit ([1994])
(65) Oosterloo & Shostak ([1993])
(66) Blackman ([1983])
(67) Marcelin et al. ([1994])
(68) Blackman ([1979b])
(69) Buta ([1987b])
(70) Pence & Blackman ([1984])
(71) Mulder & van Driel ([1993])
(72) Wong & Blitz ([2000])
(73) Liszt & Dickey ([1995])
(74) Corradi et al. ([1991])
(75) Buta & Purcell ([1998])
(76) Ryder et al. ([1996])
(77) Kaneko et al. ([1989])
(78) Ryder et al. ([1998])
(79) Comte & Duquennoy ([1982])
(80) Beckman et al. ([1986])

**Table 3.** Continued

Key for the References

(81) Duval & Monnet ([1985])
(82) Burbidge et al. ([1960])
(83) Alonso-Herrero et al. ([1998])
(84) Monnet et al. ([1981])
(85) Rozas et al. ([2000b])
(86) Ondrechen et al. ([1989])
(87) Burbidge & Burbidge ([1968b])
(88) Planesas et al. ([1991])
(89) Helfer & Blitz ([1995])
(90) Blackman ([1981])
(91) Burbidge et al. ([1962])
(92) Prieto et al. ([1992])
(93) Kanenko ([1997])
(94) Gottesman ([1982])
(95) Ball ([1986])
(96) Koribalski et al. ([1993])
(97) Knapen ([1997])
(98) Puerari & Dottori ([1992])
(99) Blackman ([1979a])
(100) Thean et al. ([1997])
(101) Lauberts ESO catalog. ([1982])
(102) Ma et al. ([1998])
(103) Grosbøl & Patsis ([1998])
(104) Weiner et al. ([2001])
(105) Sánchez-Portal et al. ([2000])
(106) Crocker et al. ([1996])
(107) Aguerri et al. ([2000])
(108) Begeman et al. ([1991])
(109) Atherton et al. ([1985])
(110) Knapen et al. ([1993]
(111) Rogstad & Shostak ([1971])
(112) Baldwin et al. ([1987])
(113) Bergeron et al. ([1989])
(114) Kaneko et al. ([1992])
(115) Peletier et al. ([1999])
(116) Bland-Hawthorn et al. ([1997]
(117) de Vaucouleurs ([1959])
(118) Maucherat et al. ([1984])
(119) Warner et al. ([1973])
(120) Newton ([1980])
(121) Considère & Athanassoula ([1982])
(122) Deul & van der Hulst ([1987])
(123) Corbelli & Schneider ([1997])
(124) Wilke et al. ([2000])
(125) Fridman et al. ([2001])

ESO 377-24: This is a small sized and not very inclined galaxy. The number of HII regions in the catalog is also small and both methods give a minimum at values more appropriate for a more inclined galaxy. Using secondary minima for both methods we get a reasonable agreement with the values from RC3 (1991). We finally adopt the values from the second method, which are in agreement with the photometry and close to the values of the first method.

IC 1438: The HII regions are placed mainly in the arms and the ring of this nearly face-on galaxy. The two methods are in good agreement. But as there is no background disk of HII regions, the first method may be biased by the presence of the spiral structure. We thus keep the PA from the second method, which coincides with that found by Crocker et al. (1996). For the IA we take the average of our two methods.

IC 2510: This is a galaxy of a very small apparent size. Nevertheless, as it is quite inclined, our two methods give results in good agreement and we keep the mean of the two, which is, furthermore, in good agreement with the literature values.

IC 2560: Our two methods are in good agreement for this galaxy and we adopt the mean of their values, which agrees well with the PA given in the RC3 (1991) and the Lauberts-ESO catalogs (1982), and with the IA of the former.

IC 3639: This is a nearly face-on galaxy in a small group. The catalog of HII regions is quite irregular and does not show any spiral structure. We adopt the values from our second method, which are in agreement with the PA of Hunt et al. (1999) and the average IA of all methods. Note, however, that there is a lot of dispersion around the mean values, which could mean that our estimate is not very safe.

IC 4754: This is a ringed, small size galaxy. Nearly all of the HII regions of the catalog are placed in the external ring. Our methods are in agreement for the IA and the agreement for the PA is only reasonable, but the values from the PA are poorly determined as the projected catalog looks quite round. We prefer to keep the values from the second method, which are in agreement with two of the photometric values for the PA and all the values for the IA.

IC 5240: This case is quite similar to the previous one. Again the HII regions are placed mainly in the external ring, but as the galaxy is quite inclined, both methods are in reasonable agreement. As before, we keep the values from the second method, whose PA is in excellent agreement with all the literature values, and the IA with the results of the Lauberts ESO catalog (1982).

NGC 53: The HII regions are placed only in the outer ring and their number is quite low. On the galaxy image, it seems that the inner ring is not oriented as the main disk, but along the bar. Our first method tends to circularize this ring which is not necessarily circular. So, we keep the mean values from the photometry of the RC3 (1991) and the Lauberts ESO catalog (1982).

NGC 157: This galaxy seems to be a bit irregular and this is reflected in the rich catalog of HII regions. Nevertheless the two methods are in excellent agreement between them and and in fair agreement with the literature values Thus, we keep the mean of our values.

NGC 210: The HII regions trace very well the arms and the inner ring. Our two methods are in agreement with the literature values and thus we keep the mean of our values.

NGC 598: Our two methods are in good agreement but the values that they give are not in agreement with the rest of the literature values, probably due to an incomplete sampling of the galaxy disk in the HII region catalog from Hodge (1999). Thus, we prefer to keep the mean of the kinematically derived values.

NGC 1068: The HII regions are placed only in the inner bright oval, and the values obtained using both methods, while in agreement, are inadequate. The values given by Sánchez-Portal et al. (2000) also pertain to the inner bright oval. Thus, we take the mean of the values from the velocity fields.

NGC 1097: Our two methods agree well for the values of IA, but the discrepancy is higher for the PA. The first method gives rounder arms, so its PA and IA values must have been highly influenced by a Stocke’s effect (Stocke 1955), while the second gives a rounder central part. These latter values agree very well with the HI kinematical values from Ondrechen (1989) as well as with three of the photometrical estimates, so we will adopt the values from the second method.

NGC 1386: Our two methods give identical results for this quite inclined galaxy, which are furthermore in agreement with the photometric estimates. We adopt the values from our two methods.

NGC 1433: The HII regions trace very well the inner ring of this galaxy. Both methods try to circularize this inner ring giving a strong disagreement with the kinematical values. We adopt the values from the velocity fields.

NGC 1566: This galaxy was also studied in the first paper, where we used the catalog by Comte et al. (1979) which traces also the external arms. For this new catalog, the HII regions are placed mainly in the inner oval part and the results of our methods disagree. The values obtained from the first catalog by GGA (1991) are in good agreement with the values from the kinematics, so we adopt the mean values of the GGA values and the optical velocity field from Pence et al. (1990).

NGC 1667: This galaxy has a small apparent size, with a catalog with a low number of HII regions. Nevertheless, as the galaxy is quite inclined, the two methods are in reasonable agreement and we give the mean of both methods.

NGC 1672: Our second method does not converge, probably due to the strong bar present in this galaxy. On the other hand our first method gives a PA value in good agreement with the photometric values form RC3 (1991) and the Lauberts-ESO catalogs (1982), but the value obtained for the IA value seems too high. We keep the values from the RC3 catalog.

NGC 1808: There is a good agreement between the two methods, but the HII regions trace only the inner bright oval part and there are no regions in the outer arms or disk. The outer disk in the galaxy image seems to be much less inclined. For this reason we prefer to keep the kinematic values from Koribalski et al. (1993).

NGC 1832: This galaxy was studied also in the first paper, but using a catalog with a low number of HII regions. Using this new catalog, the two methods are in good agreement, and there is a rough general agreement with the rest of the values from the literature. Thus we keep the mean of our two methods.

NGC 2985: The HII region distribution is quite irregular, but despite this fact, the first method gives values in reasonable agreement with the RC3 (1991) catalog. The second method does not work. We adopt the mean between our first method and RC3 (1991).

NGC 2997: This galaxy was also studied in the first paper using a similar catalog. Using the new catalog we find values for the IA that are in reasonable agreement between them, while the values for the PA are not so well constrained. The mean of the two methods are in agreement with the kinematical values from Milliard & Marcelin (1981) and the photometric values from the RC3 (1991) and, to a lesser extent, with the rest of the values. We adopt the mean of our two methods.

NGC 3081: For this galaxy we have two catalogs with distributions of similar shape, the HII regions being mainly in the inner ring. As both methods try to circularize this ring we prefer to adopt the mean of the values from the photometry and kinematics from Buta & Purcell (1998).

NGC 3198: There is a good agreement between our two methods for this quite inclined galaxy. There is also a general agreement with the rest of methods. The projected HII region distribution, however, seems somewhat irregular, and this may bias our two methods, giving higher values from the PA. For this reason we prefer to adopt the mean values from the HI kinematical studies of Bosma (1981) and Begeman (1987). Note that these are in good agreement with our second method and reasonable agreement with the first.

NGC 3359: Our methods are not adequate for this galaxy because a lot of HII regions are located in the bar region. We thus keep the mean of the kinematical values from the H alpha velocity field from Rozas et al. (2000b) and HI velocity fields from Gottesman (1982) and Ball (1986).

NGC 3367: The values given by the various methods cover a broad range of values. Our two methods give the same value for the IA, which is furthermore in agreement with the value from Danver (1942). The average of the two values of the PA are in agreement with the photometry from Grosbøl (1985). We thus adopt the mean of our two methods.

NGC 3393: The situation for this galaxy is highly unsatisfactory. The PA of 160 is mainly reflecting the orientation of the bar, so it can be dismissed. The estimate of 41 degrees comes from the outer isophote, but this seems to be heavily distorted, partly by the arms. Our methods should suffer from Stocke’s effect (1955). Since our purpose in the following pages will mainly be to study the spiral structure and our two methods agree well, we will adopt their average for our future work. We stress, however, that this is due to the lack of any better estimate.

NGC 3631: This is a nearly face-on galaxy, and thus although we use a very rich catalog, the values of PA and IA are not very well constrained. We adopt the value of the PA derived in the kinematical analysis of Knapen (1997). However, the kinematic analysis did not give a value for the IA, so we adopt the mean of our methods for this angle, which is in rough average with the photometric values.

NGC 3660: The catalog of HII regions is quite poor and the values of PA and IA are not very well constrained. Nevertheless, the two methods are in good agreement and in rough agreement with the photometric values from RC3 (1991). We adopt the mean of our two methods.

NGC 3783: The HII regions of this catalog populate an inner ring. Nevertheless, our two methods are in good agreement with the only PA value that we found in the literature and with the IA of RC3 (1991). There is also a rough agreement with the IA values from other studies. We adopt the mean of our methods.

NGC 3982: This is a small apparent size galaxy nearly face-on and the HII region catalog is quite poor. Both our methods have two clear minima, however, and are in good agreement between them. Moreover, they are in rough agreement with the photometry, so we adopt the mean values of all methods.

NGC 4051: The HII region distribution is somewhat irregular and the first method gives results only in rough agreement with the values from the second method. We finally adopt the kinematical values of Listz & Dickey (1995), which are in general agreement with most of the photometric values.

NGC 4123: The number of HII regions is quite low and the HII region distribution traces mainly the bar region. The first method does not work properly, so should be neglected. The values from our second method are in good agreement with the values from the kinematics. Seen the poor quality of the HII region catalog we adopt the mean values from the kinematics.

NGC 4258: As our two methods are in agreement for this quite inclined galaxy we adopt their mean value which is in agreement with the results of the velocity fields of van Albada (1980) and van Albada & Shane (1975).

NGC 4321 (M100): This galaxy is not very inclined and thus the value of the PA is not well constrained. On the other hand, there is a rough agreement about the IA for the rest of the methods. We adopt the kinematical values of Guhatakurta (1988).

NGC 4507: The galaxy has a small size and the HII regions populate a ring. Our two methods do not work properly because they try to circularize the ring. We adopt the deprojection angles obtained in the photometric study of Schmitt & Kinney (2000).

NGC 4593: This is a strongly barred galaxy for which there are three published catalogs of HII regions. Our two methods are in good agreement for the richer catalogs but the first method gives discordant results in the second catalog and the second method does not work at all. Thus we discard the values from the second catalog. The mean of our values are also in general agreement with the photometric values, except for the case of the I photometry by Schmitt & Kinney (2000) who give a higher PA value than the rest. We adopt the mean values of the results of our two methods applied to the first and third catalog.

NGC 4602: All values of the PA are in rough agreement, except for the value given by Mathewson & Ford (1996), which by eyeball estimate does not look very reasonable. We adopt an average value of our two methods and both catalogs, which also agrees with RC3 (1991) and Danver (1942).

NGC 4639: There is good agreement between the values obtained by our methods. Thus, we take the average values. This is also in agreement with the literature values.

NGC 4699: We adopt the average of our two methods, which is in good agreement with the photometric values.

NGC 4736: For this galaxy, we have two catalogs. In both cases, nearly all the HII regions are placed in the external ring. Our four results are only in rough agreement and they are, furthermore, not very reliable since they pertain to the ring. Thus, we prefer to adopt, the mean values given from the velocity fields (Bosma et al. 1977, Mulder & van Driel 1993, Buta 1988) which are in good agreement between them and also with the average of our two methods and the two catalogs.

NGC 4939: We have two catalogs of similar richness for this galaxy. It is quite inclined and the two methods are in rough agreement for both catalogs. We take the averages of our two methods and the two catalogs, which is in agreement with the photometric values and the value given in GGA (1991).

NGC 4995: Our two methods give identical results, which we adopt, since they are also in good agreement with the photometric values from RC3 (1991) and Grosbøl (1985).

NGC 5033: A number of estimates are available for the deprojection angles of this galaxy, and all cluster in a relatively narrow range of values. The results of our two methods are in good agreement between them and with the rest of the estimates. The deprojection of the HII region distribution is particularly sensitive to the adopted value of the IA. We tired several averages of the individual estimates both straight and weighted by our judgment of the quality which resulted in identical values. analysis of the velocity fields. Note that they are also similar to some of the derived photometric values. The deprojected galaxy using our values looks quite good, as already noted in GGA (1991). There is, however, a secondary minimum, which is in agreement with the values derived from the velocity fields. With these values we get also a round deprojected galaxy. We adopt the value from Rots et al. (1990), which are as stated, in agreement with the average of the secondary minima value.

NGC 5364: We take the average values from our two methods, which is in agreement with the rest of the values in the literature.

NGC 5371: The galaxy was too big to fit in the CCD frame used by Gonzàlez-Delgado et al. (1997), so that, the PA values found using this catalog can not be very reliable. We thus adopt for this galaxy an average of the photometric values.

NGC 5427: Here the two methods and the three catalogs give different results, which again are very different from the literature values. This is not surprising as the galaxy is not very inclined and there is no derived velocity field in the literature. For lack of any stronger criteria and looking at the deprojected images obtained with all these values, we decided to adopt the result of the first method and the richer catalog. However, it should be stressed that these are very ill defined values.

NGC 5457 (M101): This galaxy is nearly face-on. Thus, the values of the PA are not well constrained. Our methods prefer a galaxy completely face on but, as the galaxy is quite asymmetrical, we have decided to adopt the values obtained by the HI high resolution study of Bosma et al. (1981).

NGC 5643: The catalog of HII regions has an irregular distribution. The outer parts look also irregular in the galaxy images. Thus, our two methods as well as the photometric values are very unsafe. For lack of any stronger criteria, we adopt the results of the first method, which give a rounder deprojected object. It should nevertheless stressed that is a very unsafe estimate.

NGC 5861: There are very few HII regions in this catalog, so we adopt the values given by Grosbøl & Patsis (1998). It should, nevertheless be noted that, although the catalog is poor, our results are in fair agreement with the photometric ones.

NGC 6070: There is a good agreement between our two methods and the results available in the literature. We adopt the average of our two methods.

NGC 6118: For this galaxy we have, as in the former case, a good agreement between our methods and the literature values. Thus, we adopt the average of our two methods.

NGC 6221: The HII regions trace mainly the arms and give a rather irregular distribution, so that our second method is not reliable. There is a good agreement between our first method and the photometric value from Pence & Blackman (1984). We finally adopt our first method values. Note that the IA is in good agreement with the remaining photometric values.

NGC 6300: The results of the kinematical values of Ryder et al. (1996) and of Buta (1987b) are in perfect agreement, so we adopt these values. Our two methods are less reliable, since the HII regions are mainly lying in a ring for both catalogs. Nevertheless, it is worth noting that there is a reasonable agreement between our values and the adopted ones and also with the rest of the values.

NGC 6384: Our two methods agree between them and we have adopted the average of their values. Our IA values agree well with the photometric ones, while the PA does so reasonably well. The IA given by Prieto et al. (1992) seems more reliable than that of Sánchez-Portal et al. (2000), since the data extend further out in the region which is less influenced by the oval bar. This agrees with the mean of our values. The PA we adopt is somewhat higher than those given by the photometry. The deprojected catalog, however, has a round shape and thus we keep our values.

NGC 6753: Our two methods agree reasonably well between them, so we take the average values which are in good agreement with the photometric values.

NGC 6764: Our two methods give identical results and also agree quite well with the available photometric values, so we adopt our values.

NGC 6782: We adopt the average of our two methods, which is in reasonable agreement with the photometric values, as in the previous galaxy.

NGC 6814: This is a nearly face-on galaxy and as a result the values of the angles are not well constrained. We have two catalogs of different richness. As the PA can not be well constrained using our methods, we have decided to adopt the values from the kinematics of Listz & Dickey (1995) which are in fair agreement with the values obtained by our methods for the less rich catalog from Evans et al. (1996). Note that the richer catalog of Knapen et al. (1993) has a well delineated strong northern arm which can bias our results.

NGC 6902: We adopt the average of our two methods which is in good agreement with the results given in the RC3 (1991) catalog, and agrees also with the average of the rest of the literature determinations.

NGC 6935: The HII regions trace the outer ring only. Our second method does not work, and converges to a value with too high inclination, so we neglect it. We adopt the result from the first method which is in good agreement with the inclination of the RC3 (1991) catalog.

NGC 6937: No reasonable minimum was found by the first method and we adopt the values from the second method, which agree well with the inclination of the RC3 catalog, but not so well with the values quoted by Crocker et al. (1996).

NGC 6951: We take the average of our two values which are in good agreement with the values derived by Grosbøl (1985).

NGC 7020: The few available estimates agree well with our two methods, so we take the average of our two values.

NGC 7098: Our two methods try to circularize the inner ring so that, even though they agree well between them, they are not very meaningful. We thus adopt the average of the photometric results.

NGC 7219: The first method does not work very well, so we list a secondary minimum. Our adopted values are the average of the two methods and are in reasonable agreement with the few available literature values.

NGC 7267: The few HII regions are mainly in and around the bar and not in the surrounding disc. We thus adopt, the value given by Crocker et al. (1996), which is in reasonable agreement with the other photometrically determined estimates.

NGC 7314: Our two methods applied to the two catalogs give results in very good agreement. We thus adopt their mean value, which is also in good agreement with the few results available in the literature.

NGC 7329: Our second method converges to an inclination angle which seems too large. We thus neglect it and take the result of the first method, which is in reasonable agreement with the little that is available in the literature.

NGC 7331: The results of our two methods agree very well between them, and with the main kinematic estimates. We thus adopt the average of our two methods.

NGC 7479: This is a difficult galaxy since, on top of a bar, there is a major m = 1 asymmetry, clearly seen in the deprojected image for both catalogs. This can bias our methods, thus we prefer to adopt the kinematical value from Laine & Gottesman (1998), which is in good agreement with the results given by our second method.

NGC 7531: This galaxy is quite inclined, so it is crucial for the PA to be accurate. Our first method gives a value which is, by visual inspection, not acceptable. We thus adopt the result of our second method, which is in good agreement with the kinematic values.

NGC 7552: The HII regions are mainly concentrated in and around the bar region and thus can not give useful information for the deprojection. We thus adopt the values from RC3 (1991).

NGC 7590: Our two methods give results that coincide, so we adopt their average values, as they are also in reasonable agreement with the few available photometric estimates.