110 Dentition of Pulmonate Mollusks. 
ing beyond the base of attachment; marginals bicuspid, cusps short, bluntly 
rounded, the inner one, as usual, the longer, each bearing short cutting 
points. 
Stylodon. 
I have shown H. militaris, Pfy., placed in this genus by 
von Martens, to be a Nanna. 
Stylodon Studeriana, Fér. Seychelles. Consul Pike. 
Jaw stout, strongly arched, ends but little attenuated, blunt; anterior sur- 
face without ribs ; there are, however, a few coarse, broad, vertical wrinkles. 
One jaw had a slightly developed median projection to its cutting edge, 
another has no approach to a projection. 
Plate VIII, fig. M, shows the lingual dentition; teeth 69-1-69, with about 
22 laterals on each side. There is considerable resemblance to the dentition 
of Merope fringilla described below. The cutting points on centrals and — 
laterals are, however, more pointed. ‘There are no side cusps or cutting 
points to centrals or inner laterals; the outer laterals and marginals have 
very oblique, broad, bluntly trifid cutting points. 
Dentellaria. 
In this genus,.the presence or absence of ribs on the jaw is 
not a reliable generic character. 
I have examined a large proportion of the known species. 
The jaw varies somewhat, so that each description should be 
studied. There seems a tendency to a median projection to the 
cutting edge, and to the presence of ribs. D. pachygastra, Gray, 
has seven decided ribs and no median projection; orbiculata, 
Fér., has traces of ribs and no median projection; Jsabella, 
Fér., has decided ribs and no median projection; denfiens, 
Fér., has decided ribs and no median projection; neleola, 
Rang., has one decided rib and a median projection; dadia has 
eight decided ribs; formosa, Fér., has no ribs, but a strong 
median projection; perplexa, Feér., has obsolete ribs and median 
projection ; dychnuchus, same as last; punctata, Born, has 
median projection and decided ribs ; Josephine, Fer., is strongly 
arched, has no ribs, but a median projection. 
The species agree in their dentition. 
Dentellaria orbiculata, Feér. 
Jaw striated, thick, slightly arched, ends squarely truncated; cutting 
edge irregular, showing traces of the ends of subobsolete ribs, no median 
projection. (Pl. XVI, fig. W.) 
