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I.

A recent paper has given an outline of a revised system of classification of the forms of galaxies, together with types for 608 systems. 1 That investigation will be designated Paper I, and the present one Paper II.

The galaxies classified on the revised Yerkes system in Paper I include a large fraction of the northern entries in the Shapley-Ames Catalogue. It seemed advisable to make the classification approximately complete to some limiting apparent magnitude; a program was therefore devised to classify a number of additional galaxies. Through the kindness of Dr. I. S. Bowen and the Committee of the Mount Wilson and Palomar Observatories, I was permitted to make use of the original negatives of the National Geographic Society-Palomar Observatory Sky Survey for the purpose.

The present paper completes the classification of all galaxies brighter than magnitude 13.1 in the Shapley-Ames Catalogue and north of delta = -25°, with two exceptions: the object NGC 2149 has been omitted from the catalogue, since it appears to be a diffuse nebulosity, rather than a galaxy; NGC 2798 was omitted inadvertently.

The galaxies included in the present paper were classified on the 48-inch Sky Survey plates during a period as guest investigator at Pasadena in the autumn of 1958. A large number of galaxies in Paper I were reclassified without knowledge as to the earlier type assigned; this overlap furnishes material for an accurate determination of the systematic characteristics of the two series.

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