[ LAMBE | ON A NEW CROCODILIAN GENUS 235 
under surface. Its front and back edges are sharp, the lateral ones 
comparatively thick. 
The long very deeply pitted scute represented in fig. 18, has a 
slightly convex under surface. Its edges are slightly irregular, not 
very thin and nowhere exhibit what would constitute a sutural surface. 
A supposed ventral scute, fig. 23, has uo kee!; it is al.nost square 
and slightly convex above and below. It thins toward the edges but 
much less toward one side (the left in the figure) where the edge is, at 
its mid-length, about 2.5 mm. thick and evidently forms a definite 
sutural surface. ‘Th's scute may be one of two picces composing a 
compound ventral plate similar to those of species of Diplocynoden. 
Two scutes, plate V, figs. 21 and 22, are conspicuous on account 
of their size. One fig. 21, is very decidedly bent so as to be trans- 
versely very concave beneath. A short longitudinal keel is developed 
and: laterally the edges remain thick and rugese. The other is flat 
below, is without a keel, and no evidence of sutural contact with other 
seutes is recognizable; it is possible that this scute is from the upper 
surface of the neck and formed part of a neck-shield. 
The maximum thickness of each of the scutes figured in plate V 
is given in the folowing measurements :—fig. 15, (cat. No. 1146), 
onu ide.) 16. (cat. No. 1705), 7.5 mm; fig: 17, (cat. No. 152%), 
5 mm.; fig. 18, (cat. No. 975), 4.5 mm.; fig. 19, (cat. Ne. 1837), 3 
mm.; fig. 20, (cat. No. 1614), 3 mm.; fig. 21 (cat. No. 377), 9 mm.; 
fig. 22, (cat. No. 960), 9.5 mm.; fig. 23, (cat. No. 869), 4 mm. ~~" 
The conclusion arrived at in a study of the Red Deer River speci- 
mens just described is that they represent a brevirostrate form of 
Eusuchia, different generically from any hitherto known, and one that 
is not readily placed in the present generally accepted classifications of 
the procælian Crocodilia. The dentition of Leidyosuchus resembles 
in some respects that of Diplocynodon, especially in the enlargement 
ef the third mandibular tooth. The reception of the fourth lower tooth 
into a notch in the maxilla is a crocodilian character shared by Diplo- 
cynodon. The form of the occiput appears to approach closer to that 
of the crocodiles than the alligators and the size of the supratemporal 
vacuities is rather crocodilian than otherwise. As a whole, the char- 
acters, brought to light by the specimens representing Leidyosuchus, 
place that genus close to those members of the Crocodilia having broad, 
short snouts and procælian vertebræ. The genus is for the present 
referred to a group such as would be provided by Lydekker’s Breviros- 
trate Division of the Crocodilide, if that division were extended so as 
to include short-nosed forms in which the splenial enters to a slight 
extent into the mandibular symphysis. 
