238 FOSSIL TURTLES OF NORTH AMERICA. 
has a height of 45 mm. All of these lie wholly on the peripherals. The fifth marginal 
suddenly rises to a height of 100 mm. and overlaps the lower ends of the second and third 
costal bones. The ninth marginal has a height of 145 mm. The next two are only slightly 
lower. The supracaudal scutes meet along the midline a dis- 
tance of 97 mm. The costal scutes diminish in size from the first 
Mer aaeanceal Ae ota to the last. The latter has a fore-and-aft length of 80 mm. and a 
width of 55 mm. 
: mee as The plastron (plate 35, fig. 2; text-fig. 297), as in other spe- 
3 100 85 cies of the genus, is relatively small. Both the anterior and the 
4 os a posterior lobes are truncated. The total length is 355 mm. The 
anterior lobe has a length of 80 mm. and a width of 175 mm. at 
the base. The truncated anterior end is 85 mm. wide. The 
entoplastron is 50 mm. long and 70 mm. wide. The bridges are 140 mm. wide. The posterior 
lobe is 130 mm. long and 175 mm. wide at the base. The posterior truncated end is about 
80 mm. wide. The free borders of both lobes are acute. The plastron articulates with the 
peripherals by means of sutures; and axillary and inguinal buttresses rise nearly to the 
Fic. 297.—Adocus punctatus. Lower side of shell. 0.16. 
ab, abdominal scute; an, anal scute; c. p.1, c. p.2, etc., costal plates; ent, entoplastron; ep7, epiplastron; fem, 
femoral scute; g, gular scute; ium, humeral scute; hyo, hyoplastron; hypo, hypoplastron; ig, intergular 
scute ; infm, inframarginal scutes; nu, nuchal bone; pec, pectoral scute; per. 3, per. 8, peripheral bones; 
py, pygal; spy, suprapygal; x/ph, xiphiplastron. 
lower ends of the costal bones. Plate 34, fig. 5, from a drawing made for Dr. Baur, repre- 
sents the upper side of the xiphiplastral Bones There are very distinct curved depressions 
for the pubic bones, but there was no sutural articulation of the latter bones with the plastron. 
The sutures between the various bones of the plastron are somewhat irregular, as is shown 
in the figures. The sulci are still more irregular, especially the longitudinal cane All the 
sulci are narrow and shallow. The intergulars have pushed the eulars away from contact at 
the midline, and neither gulars nor intergulars overlap the entoplastron. The humerals occupy 
42 mm. of the midline. The pectorals measure 40 mm. along the midline and they overlap the 
hinder end of the entoplastron. The abdominals, the femorals, and the anals respectively 
occupy 88 mm., 82 mm., and 72 mm. of the midline. There are 3 inframarginals on each of 
the bridges. 
