232 
COliYPHODON. 
an acute apex, and an internal cusp lising from anterior and posterior 
basal cino-nla. No internal nor external basal cingrula. 
I have already given a general description of the superior canine. To 
this I add, that near the base the posterior cutting-edge is replaced by two 
ridges, which inclose a shallow groove between them. The anterior one 
disappears near the middle of the crown, and the posterior becomes the 
true edge. 
The superior incisors are large, and the crowns have a longitudi¬ 
nally oval outline. They are marked with a ridge on the anterior 
internal aspect, which is so strong on the second and third as to give them 
a triangular section. - Tliey have no external basal cingulum. The crowns 
of the inferior incisors are not different in outline, but they lack the external 
longitudinal ridge, and have a weak internal basal cingulum. 
The inferior molars present neither internal nor external cingula. The 
premolars are stout and elevated; the posterior heel is scarcely recognizable 
on the first, which is equal in transverse and longitudinal diameters. The 
posterior cingulum, or heel, is as well marked on the penultimate as on the 
last molar, and is distinct on all the true molars. Like the third, the first and 
second true molars are rather elongate, and have a well-developed descend¬ 
ing anterior cres>t. The enamel of all the teeth is obsoletely rugose. 
I 
Measurements of the sJaill. 
M. 
Length from the posterior nares to the preiiiaxillary alveolar border. 0.270 
Length of the series of superior molars.. 0.148 
Length of the superior true molars.... 0.085 
Length of the horizontal portion of the premaxillary.. 0. 005 
Length from the foramen magnum to the foramen ovale. 0. 095 
Length of the basioccipital bone to the sphenoid. 0. 045 
Vertical length of the mastoid process.... 0.030 
Width of the supraoccipital region..... 0. 080 
Width of the anterior nares . 0.044 
Width of the palate at the last molai’s... .. 0. 039 
Depth of the mandible just behind the last inferior molar. 0. 055 
Width of the mandible at the same point... 0. 034 
Width of the free portion of the nasal bones at the base. 0. 024 
Length of the last upper molar .. 0. 030 
W’idth of the same.. 0. 037 
