24 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



forked, but is of the same type as in Ena {Zebrina) detrita} In its 

 other organs Gochlicopa agrees closely with both the Eninse and the 

 Valloniinee, as well as with the more typical Pupillidse. It therefore 

 seems evident that the Cochlicopidae should also be reduced to the 

 rank of a sub-family of the Pupillidse. 



Azeca is generally admitted to be closely allied to Cochlicopa, 

 which it resembles in its radula as well as in its pallial organs, etc. 

 Yet in its reproductive system the British species of Azeca difiers 

 widely from Cochlicopa.^ The receptacular duct is unbranched, 

 but the free oviduct bears an appendiculum instead. The prostate 

 gland is greatly developed, especially towards its hinder end, which 

 extends backwards beyond the albumen gland. The vas deferens 

 is unusually thick, and there is no penial appendix in the British 

 form, although Saint-Simon states that one is present in Azeca 

 menkeana alzenensis.^ In view of these striking differences between 

 the genital organs of Cochlicopa and Azeca, the latter genus might 

 well be placed in a distinct sub-family by itself. 



Leptachatina, Amastra, and the other genera that Pilsbry includes 

 in the Amastridse, have reproductive organs intermediate in 

 character between those of Cochlicopa and Azeca J They have the 

 large prostate gland and unbranched receptacular duct of Azeca, 

 but in other respects they agree exactly with Cochlicopa. The radula 

 has small central teeth, and is of the same type that we find in 

 Cochlicopa, Azeca, and the Valloniinse, and so are the pallial organs. 

 Further, the shell in some species of Lejjtachatina, the most primitive 

 of these genera, is remarkably like that of Cochlicopa. Indeed, 

 Pilsbry himself says that " so far as the groups are known, no 

 character of importance separates Cochlicopa from Leptachatina ".* 

 He modified this statement later by saying that the Amastridse 

 could be distinguished from the European forms by one character, 

 namely the prostate gland,® but we have seen that this is not so, as 

 Azeca has a large prostate like the Amastridse. Therefore, in the 

 present state of our knowledge there would appear to be no 

 justification whatever for placing Cochlicopa and Azeca in one family 

 and Leptachatina and Amastra in another. I therefore consider 

 that the Amastridse might also be reduced to the rank of a sub- 

 family of the Pupillidse and placed next to the Cochlicopinse and 

 the Azecinse. 



1 Beck, Jenaische Zeitschr. Naturw., vol. xlviii, 1912, pi. ix, fig. 25a. 

 In most of the Eninas the penial retractor is bifurcated, as in Vallonia, 

 Acanthinula, etc. ; but the fork varies in size, being very small in E. obscura, 

 though larger in E. montana. 



2 See Boycott, Journ. of Conch., vol. xvi, 1919, p. 53. 

 2 Annales de Malacologie, vol. i, 1870, p. 29. 



* Excepting in regard to the radula, my knowledge of the anatomy of these 

 snails from the Hawaiian Islands is derived almost entirely from Pilsbry's 

 excellent account in the Manual of Gonchology (2nd ser.), vol. xxiii, 1915, 

 pp. 57-68, pis. xii-xvii, xx, and xxii. 



* Op. cit., vol. xix, 1908, p. 212. 

 6 Ibid., vol. xxiii, 1915, p. 62. 



