On Prophysaon, etc. 305 



to the vas deferens, a short distance before the latter organ 

 enters the penis, which it does at the apex of the penis sac. 



]fI»crocjcliis Baudoiii, Petit. 



We have already described the lingnal membrane of this 

 species. (See Am. Journ. Conch., VII, p. 175.) Recently 

 we have received a Guadeloupe specimen (not adult), from 

 Mr. Schramm. On extracting the lingual membrane we 

 found attached to it a most delicate, transparent, colorless 

 jaw, arched, with pointed ends, median projection to cutting 

 edge and smooth anterior surface. 



This, added to "the lingual dentition, places the species in 

 Maci'ocycUs. 



Biilimiiliiis miiltifjnscisitiis, Lam. (Liostracus.) 



Antigua. Governor Rawson. 



Jaw long, very low, slightly arcuate ; ends attenuated, pointed ; ex- 

 tremely thin, transparent; divided by numerous delicate ribs into over 

 thirty plates of the form common to Bulimulus, Cylindrella, etc., the 

 upper median plates triangular. 



Lingual membrane broad. Teeth in numerous waving rows, of the 

 type we have described and figured in Bulimulus laticincttis. (Ann. Lye. 

 Nat. Hist., N. Y., X, p. 81, pi. ii, fig. 1, 5.) The centrals are distinctly 

 trifid. 



BllliiuiiliiS alternansi, Beck. {Liostracus.) 



Islands in the Bay of Panama. Mr. McNiel. 



Jaw long, low, slightly arcuate, extremely thin and transparent; divided, 

 by numerous delicate ribs in about fifty-two plates of the type common in 

 Bulimuhis, Cylindrella, etc. 



Lingual membrane as in the preceding species. 



Helix l>stcliygrastrst, Gray. (Dentellaria.) 



Guadeloupe. Mr. Schramm. 



Jaw stout, slightly arcuate, ends blunt ; anterior surface with decided 

 ribs, denticulating either margin, about seven, irregularly disposed; both 

 ends free from ribs. 



Lingual membrane as usual in the subgenus ; see above, p. 303 and plate 

 xiv, figs. 7, 8, for those of Helix lychnuchus. 



