GLIRES OF THE SANTA CRUZ BEDS. 475 



the ventral branch of the maxillary zygomatic process, is more slender 

 and that the rostrum is longer and narrower. The mandible has low and 

 narrow horizontal rami. 



An account of the bones of the skeleton has already been given in the 

 generic description, which is principally taken from this particular speci- 

 men, though in several other species more or fewer of the limb bones 



FIG. 47. 



CL 



Eocardia excavata, lower grinding teeth, external and crown views, x |. a. Right side. b. 

 Left side of same individual (No. 15,211). 



have been obtained and serve for purposes of comparison. Aside from 

 the size and slenderness of the bones in this species, the only character 

 which should be emphasized is the stoutness of the fibula, which has a 

 thicker shaft than in E. perforata. 



In the following table all the dimensions are taken from the skeleton, 



No. 15,211. 



MEASUREMENTS. 



Upper dentition, length pA-mS- 017 Mandible, length from condyle 045 



Upper incisor, width 0025 ." depth at p^ ' .008 



Atlas, length oio 



" width 02 1 



Axis, length of centrum 009 



" width of anterior face Ol I 



" height to tip of spine 017 



Lumbars 5-8, inclusive, length 064 



Last lumbar, width of posterior face . . .009 



" thickness 003 



P, length (/. e., antero-posterior diam- 

 eter) 003 



PA, width (i. e., transverse diameter). . .0026 



M-3-, length 005 



" width 004 



Lower dentition, length 0345 



" P 5 -m 3 OI 75 



Lower incisor, width 0025 



" " thickness 003 



P ? , length 0035 



" width of anterior prism 003 



Occiput, height 017 



" " width at base 022 



Zygomatic arch, length 035 



Palate, width at p*. 0055 



" " " m^. . .008 



Last lumbar, width over transverse 



processes ?-O3O 



Sacrum, length 03 1 



" width over pleurapophyses . . .027 



Scapula, length 043 



" greatest width 02 1 



" distal width oil 



Humerus, length 052 



" proximal width 009 



" distal width 009 



