Dentition of Pulmonate Mollusks. 115 
tachment is carried beyond the reflection in the centrals; teeth stout, with 
stout cusps and cutting points. 
Borus oblongus, var. albus, Mull. Tobago. Goy. Rawson. 
Jaw slightly arcuate, stout, wide, of almost equal height throughout; 
ends but slightly attenuated, blunt; anterior surface with vertical and 
transverse striz and perpendicular wrinkles, scarcely distinguishable from 
the ribs, of which there are ten well-developed, crenulating either margin. 
Lingual dentition as published by Heynemann for B. oblongus in Mal. 
Blatt., 1868. 
Orphnus Hanleyi, Pfr. Brazil. J. G. Anthony. 
Jaw stout, strongly arched, transversly striate; ends but little attenuated, 
blunt; cutting edge with a broad, stout, striated median projection. 
Lingual membrane (Pl. XI, fig. D) long and narrow; teeth 50-1-50; the 
lower margin of the base of attachment is excavated in centrals and lat- 
erals; no side cusps or cutting points. 
Orphnus foveolatus, Rve. Northern Peru. Prof. Orton. 
Jaw slightly arched, wide, low, thin, with over 50 delicate ribs of the 
kind described below under bulimulus Lobbi, Rve. 
Lingual membrane (Pl. XI, fig. C) long and narrow, with 34-1-34 teeth; 
no side cusps or cutting points to centrals and laterals; reflection short, 
stout; the membrane is of the same width to its abruptly truncated ends, 
and very thick. 
Orphnus magnificus, Grat. Brazil. 
Jaw stout, low, wide, slightly arched, ends slightly attenuated, blunt; 
entire anterior surface covered with numerous stout ribs, breaking the 
regularity of both upper and lower margin, but not actually denticulating 
them. , 
Lingual membrane long, rather broad, with 30-1-30 teeth. Teeth as in 
0. Hanleyi. 
Dryptus pardalis, Fer. 
Jaw thick, low, wide, slightly arcuate, ends but slightly attenuated, 
blunt ; whole anterior surface occupied by 12 broad ribs, denticulating 
either margin. 
Lingual membrane not examined. 
Dryptus marmoratus, Diinker. 
Lingual membrane (PI. XJ, fig. E) long and broad; no side cusps or cut- 
ting points. 
Eurytus aulacostylus, Pfr. St. Vincent. Gov. Rawson. 
Jaw thin, transparent, slightly arcuate, with about sixty delicate ribs, as 
