van den Bergh [196], following Baade [9], proposed that the lenticular class of galaxies did not form transition classification between spirals and ellipticals but rather they represent an extreme sequence parallel to normal spirals, where all members of the non-elliptical class are distinguished by means of their disk-to-bulge ratio: ``early-type'' spirals having large bulges, ``late-type'' spirals having small bulges. A sequence of ``anemic spirals'' (typed Aa-Ab-Ac, and found most frequently in clusters) is suggested to populate a sequence intermediate between the gas-rich normal spirals (typed Sa-Sb-Sc) and the gas-poor lenticular systems of type S0 (typed S0a-S0b-S0c).