NATURAL SCIENCES OF PHILADELPHIA. 5t 



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median projection. All have lingual dentition such as I figure 

 of graminicola (plate X., fig. 8). 



Liochila. — As stated already (p. 56) H. picta^ Born, must be 

 removed from this subgenus to Polymita, probably also H. sulphu- 

 rosa, Mor. 



Eurycratera has decided stout ribs on its jaw. "We have seen 

 H. crispata, Fer. (Am. Journ. Conch., VII. 119), and H. angulata, 

 ¥4r. (this paper, p. 50). The lingual dentition is essentially the 

 same in each, but on account of difference in the development of 

 the points of the side cusp, I figure that of each (pi. IX. fig. 5; 

 pi. X. fig. 9). 



Polydonles has the same type of dentition, as in the last sub- 

 genus, as shown in my figure of H. Luquillensis, Shuttl. (plate X., 

 fig. 2-4) the only species examined by us. Jaw not seen. 



Stylodon. — We have shown H. militarHs, Pfr. to be a Nanina 

 (Ann. N. Y. Lye, x. 169). Other species unexamined by us. 



Erepta. — The same may be said of H. stylodon^ Pfr. (see ante, p. 

 48), and leucosfyla, Pfr., and rufizonata, H. Ad. (Ann. N. Y. Lye, 

 x. 169), all Mauritius species. 



Dentellarna. — We have examined a large proportion of the 

 known species. The jaw varies somewhat, so that each descrip- 

 tion should be studied. There seems a tendency to a median pro- 

 jection to the cutting edge, and to the presence of ribs. H.pachy- 

 gastra, Gray (Ann. N. Y. Lye, x. 305) has 7 decided ribs and no 

 median projection. H. oi'biculata, Fer. (Am. Journ. Conch., VI. 

 205, pi. ix. f. 14) has traces of ribs and no median projection. H. 

 Isabella, Fer. (1. c. VII. 1Y9) has decided ribs and no median pro- 

 jection. H.dentiens, Fer. (Am. Journ. Conch., VII. 1*79) has de- 

 cided ribs and no median projection. H. nucleola, Rang (ante, 

 p. 52) has one decided rib and a median projection. H. badia 

 (ante, p. 52) has 8 decided ribs. H. formosa, Fer. (ante, p. 52) 

 has no ribs, but a strong median projection. //. pej^plexa, Fer. 

 (Ann. N. Y. Lye, x. 221) has obsolete ribs and median projection. 

 H. lychnuchus, same as last (Ann. N. Y. Lye, x. 221, pi. xiv. f. 5, 

 7). H. punctata, Born (ante, p. 52) has median projection and 

 decided ribs. H. Josephinae, Fer. (Ann. N. Y. Lye, x. 306) is 

 strongly arched, has no ribs, but a median projection. 



All the above species agree in their dentition. See figure of 

 that of lychnuchus (1. e) and of punctata (plate IX., fig. 8 of this 

 paper.) 



