172 PROCEEDINGS OF THE HALACOLOGICAL SOCIETY. 



stands nearest. I would suggest that its position is between Paryphanta 

 and Rhytida, possessing certain of the features of each, hut, in the 

 sum-total, agreeing with neither. 



Sehizoylossa. — Hedley, in describing the genus, pointed out its 

 position, and suggested Paryphanta as the nearest of kin. The 

 correctness of this view seems to the writer abundantly proved. With 

 P. Hoehstetteri, Pfr., it agrees in the shape of the foot, the shallow 

 grooves proceeding from the lips and extending around the foot- 

 margin ; it also exhibits a very similar dentition. The modified pedal 

 cavity, the reduced lappets on the mantle, and the periostracal covering 

 of the shell are, I submit, evidence of relationship. Suter states it is 

 evidently a Paryphanta in which the shell has become vestigial, but 

 he does not support the statement with any evidence. The peculiar 

 muscular attachment with the shell suggests degeneration. The posterior 

 position of the muscle attached to the columella would not of itself give 

 to an auriform shell, that secure attachment necessary to an animal 

 whose habitat is amidst a tangled decaying vegetation. The narrow 

 muscle on the left side adds considerably to the security of the shell, 

 and 1 regard it as the more recent development, due to a change in 

 condition, a link in the evidence of degeneration from the more 

 helicoid form to the existing slug -like animal. Compared with 

 lestacella haliotidea, Drap., the difference is almost complete, the 

 nervous system alone showing any near resemblance. 



Note. — Since writing the above paper Mr. M. F. Woodward has 

 directed my attention to the hermaphrodite duct, and queries the 

 presence of an appendix thereto. 



A careful scrutiny proves that in Rhytida Greenwoodi there is an 

 appendix ; it is situated close to the albumen gland, is about l'5mm, 

 in length, and much resembles a convolution of the hermaphrodite 

 duct. In Paryphanta Hoehstetteri it does not occur, and I failed to 

 find any trace of it in Sehizoylossa Novoseelandica. An animal of the 

 latter species contained within the sacculation of the uterus six fully 

 developed eggs with calcareous shells. I may also mention that in 

 several species of Flammulina there is an appendix to the hermaphrodite 

 duct ; it is imbedded in the albumen gland, and its minute apex is 

 alone visible externally. 



