348 Lingual Dentition and Anatomy of 



iitroi>lii» deciiiuitiin,* Fer. 

 Castle Island, Bahamas. 



Jaw stout, stronsily arcuate, euds slightly attenuated, bluntly rounded; 

 anterior surface ribless, transversely striate, and with several stout lines 

 of reinforcement; a small, blunt, median projection to cutting edge.' 

 (See our fig. 431, p. 247, of L. and F. Wi Shells, I, for jaw of 8. incana.) 



Lingual membrane as usual in the IlelicidcB. Teeth about 30-l-30> 

 about as broad as long, short, broad, with short, stout, bluntly pointed 

 median cusps and subol)solete side cusps, upper margin of teeth rounded. 

 Marginal teeth simply a modification of the lateral, with one inner, large, 

 and one outer, small, stout, blunt, oblique denticle. 



Ktropliist Tliiniist, Brug. var. ? 

 Abaco, Bahamas (also Cuba). 



Jaw slightly arcuate, stout, rough, rather high, ends but little attenu- 

 ated, blunt; cutting edge with a wide, blunt, slightly developed median 

 projection. 



Lingual membrane with about 30-1-30 teeth. Centrals short and broad, 

 the upper margin rounded and reflected into a short, broad cutting projec- 

 tion, with one stout, short, median cusp, bearing a stout point, and sub- 

 obsolete side cusps. Laterals like the centrals, but bicuspid and unsym- 

 metrical. Marginals long, low, with irregular, short, blunt, oblique, 

 stout denticles, usually about four, the inner two the largest. 



Puptt fstllax. Say (LeucocJiila). 



We are indebted to Mr. A. G. Wetherby for Ohio speci- 

 mens, from which we extracted the jaw and lingual membrane 

 here described. 



Jaw wide, low, slightly arcuate, ends blunt, but little attenuated. 



Lingual membrane as usual in the genus. (See our L. and F. W. Shells 

 of N. A., 1, p. 233, figs. 395, 401, 409.) Teeth about 15-1-15, with about 

 seven perfect laterals. Centrals quite narrow, the reflected portion very 

 small, tricuspid. Laterals quite broad, bicuspid. Marginals quadrate, low, 

 wide, with one inner, long, oblique, blunt denticle, and several outer, 

 small, irregulac, blunt denticles. The outer lower edges of the centrals 

 and laterals have the projecting or short reinforcements shown in the fig- 

 ures referred to above. 



• See remarks on this species by M. Crosse, in Journ. de Conch, VIII, 3d Ser., p. 337, 

 18C8. 



