EMYDID:. 31 I 
is 82 mm.; the width, 143 mm. Thus the length is only 55 per cent. of the width. The epi- 
plastral lip is 55 mm. wide and projects but little beyond the general curve of the lobe. The 
beveled surface on each side of the lip (fig. 396) on the upper erate of the bone is only 15 mm. 
wide and at the hyoepiplastral suture only 12mm. The thickened portion of the epiplastrals 
above the lip extends backward only 16 mm., and where thickest, just mesiad of the gular 
sulci, only 15 mm. ‘The free borders of the lobe are acute nearly to the lip. The entoplastron 
is lozenge- shaped, 51 mm. long and 65 mm. wide. The bridge is 133 mm. wide. 
The posterior lobe is g8 mm. long and 135 mm. wide, fie length being thus about 73 per 
cent. of the width. The width is considerably less than the half of the length of the plastron. 
In the type of £. jeanesi: the width is close to half the plastral length. Posteriorly in No. 5988 
there is a broad notch. The beveled surfaces along the borders on the upper side (fig. 397) 
390. 400. 
390. 397. 401. 
Fics. 396-401.—Echmatemys wyomingensts. Various bones. 
396. Upper surface of epiplastral lip. <4. No. 5988 A. M.N.H. 
397- a! surface of right side of hinder lobe of plastron. 4. No. 5988 A. M.N.H. 
398. Left dentary bone, outer surface. X$. No. 5968 A. M.N.H. 
399. Same dentary as fig. 398, seen from above. 3. 
400. Upper surface of anterior lobe. <4. No. 6o10 A. M.N.H. 
4o1. Upper surface of free border of hinder lobe of plastron. <4. No. 6o10 A. M.N.H. 
have a width of 18 mm. at the hypoxiphiplastral sutures. Here the thickness of the bones is 
14mm. 
The gular scutes are 39 mm. long; the humerals, 36 mm.; the pectorals, 51 mm.; the 
abdominals, 84 mm.; the femorals, 58 mm.; the anals, 37 mm.; all measured along the mid- 
line. he axillary scute falls far short of reaching back to the fifth marginal; the inguinal 
comes forward nearly to the sixth marginal. 
The posterior buttresses extend ward from the free borders of the hinder lobe little more 
than one-third the distance to the midline. Articulating with the fifth and sixth costals, they 
rise about 44 mm., to a point nearly half-way from the lower border of these costals to the 
bases of the rib-heads. The anterior buttresses appear to have risen about 20 mm. within the 
first costals. 
