26 Genitalia and Lingual 



The character of the dentition, as well as the cauc'al mucus pore, proves 

 the species to be a true Zonites, and not a Macrocyclis, in which genus it 

 is placed by Tryon, Am. Journ. Conch., II, 24G. 



The existence of the dart sac and dart iias already been published. 



Zonites internus. Say. 



An examination of the animal by Mr. Bland shows the existence of a 

 dart. 



Helix rufo-apicata, Poey. (Hemitrochus.)* 



Cuba. Mr. Arango. 



Jaw slightly arcuate, ends but little attenuated, blunt; anterior surface 

 without ribs; cutting edge with a broad, blunt, median projection. 



Lingual membrane (pi. V, fig. v) long and narrow. Centrals long and 

 narrow with one median stout cusp, bearing a short, bluntly pointed 

 cutting point, the side cusps subobsolete. Laterals like the centrals, but 

 unsymmctrical. Marginals subquadrate, with one very broad, oblique, 

 acutely trifld cutting point, the central division the largest. 



The figure a gives one central tooth with two adjacent laterals, b gives 

 two extreme marginals. 



The dentition has the same general character as the other species of 

 Hemitrochus, examined by me, viz., gallopavonis, graminioola, various and 

 Troscheli. 



Helix badia, FCr. (Dentellaria.) 



Martinique. 



For jaw and dentition see Proc. Ac. Nat. Sc, Phila., 1874, p. 52. 

 Genital system resembling that of H. Josephines, herewith described. 



Helix nuxdenticulata, Chemn. {Dentellaria.) 

 Martinique. 



For description of jaw and lingual dentition see Proc. Ac. Nat. Sc. 

 Phila., 1874, p. 52. 



The genital system is figured on pi. V. fig. vin. The ovary (11) is- 

 short, stout. The oviduct (8) is wide, sac-like. The vagina is short, 

 small, with a bulbous expansion near its top; the duct of the genital 

 bladder enters at about the middle of its length, the sac of the penis near 

 its base. The penis sac (5) is very prominent. It is as long as the 



•Mr. Bland and I have elsewhere (Ann. of Lye. of Nat. Hist, of N. Y., X, 341) 

 pointed out the great difference in the lingual dentition of Helix muscarum, Lea, the 

 type of the subgenus Polymila, and the othar species referred to the subgenus by 

 von Martens. We have suggested using for the latter the name Hemitrochus. We 

 havo also shown that H.pizta belongs to the true Polymita, sharing the peculiar den- 

 tition of muscarum. 



