NATURAL SCIENCES OF PHILADELPHIA. 195 
lateral expansion of the base of attachment. Marginals (0) low, 
wide, with one inner, stout, oblique cutting point and two outer, 
smaller, blunt cutting points. 
As in all lingual membranes, there is a difference in the develop- 
ment of the cusps and cutting points on various parts. The teeth 
figured are the least graceful in their outlines. 
Genus BINNEIA, J. G. Coop. 
Jaw (fig. 40) low, arcuate, with blunt, scarcely attenuated 
ends; no median projections to the cutting edge; anterior surface 
with numerous, broad, crowded ribs. 
Bie 40: Lingual membrane (fig. 41) as usual in the Helz- 
gm cine. Centrals with a subquadrate base of attach- 
ment, with expanded lower angles; upper margin re- 
flected ; reflection large, bearing three distinct cusps, 
the central thelongest; allthree cusps apparently with 
distinct cutting points. lLaterals like the centrals but unsymme- 
trical by the suppression of the inner cusp and cutting point, and 
Jaw of Binneia 
notabilis. 
Fig. 41. 
TiC pe hs Re xe “ay 
Lingual membrane of Binneta notabilis. 
inner lower lateral expansion of the base of attachment. Margi- 
nals simply a modification of the centrals, subquadrate, higher 
than wide, with one inner, long, oblique, stout cutting point, and 
one outer, smaller, side cutting point. 
I regret not being able to give a more satisfactory figure of the 
dentition of B. notabilis, our only known species. 
It has 21—1—2]1 teeth, with 8 perfect laterals. 
Genus HEMPHILLIA, BI. and Binn. 
Jaw of the only known species, H. glandulosa, thick, low, wide, 
slightly arcuate, ends attenuated, blunt; cutting margin without 
median projection ; anterior surface with about 14 crowded, stout, 
irregularly developed ribs, denticulating either margin (pl. XVI., 
fig. 6). 
