268 FOSSIL TURTLES OF NORTH AMERICA. 
appears to be missing. The hgure presents the inner, or visceral, surface. This bone is 4 mm. 
thick at its anterior border, but toward the other border it thickens greatly, so that a little 
beyond the middle of the width the thickness is10mm. From the line of its greatest thickness 
the bone is beveled off on the inner side to its hinder border, and against this beveled surface 
the sixth costal has articulated. A strongly developt buttress from the plastron ascended 
against the inner surfaces of these two costals at their junction. The scar for this buttress on 
the fifth costal here fgured is 20 mm. long. The plastron was therefore articulated with the 
331. 330. 329. 
Fics. 329-331.—Kallistira costilata. Costals of the type. 1. 
329. Proximal end of costal, second or fourth. 
330. Proximal end of costal, showing a carina. 
31. Distal end of costal, probably the fifth, showing scar 
for inguinal buttress of plastron. 
carapace in a very different way from that seen in other dermatemyds; and a distinct genus 
is indicated, 
Portions of 3 neurals are at hand, those represented by Cope’s figs. 18, 22, and 25. The 
first-mentioned (fig. 332) has a width of 22 mm., probably belonged well forward, and was 
possibly the second. The median carina 1s barely perceptible. No sulcus crosses the portion 
present. That part of a neural from which Cope’s fig. 25 was drawn (fig. 3324) is narrow and 
devoid of a carina. It is crost near the fracture by a narrow and shallow sulcus. It appears quite 
probable that this is the posterior end of the first neural. At its lateral border it is 5 mm. thick. 
The neural represented by Cope’s fig. 22 (fig. 333) apparently belonged to the rear of the 
carapace, and resembles closely the sixth of Staurotypus saluinit. Its length is 18 mm.; 
Fics. 332-334.—Kallistira costilata. Neurals and a peripheral of type. 1. 
332, 3324. Portions of two neurals of the type. 332 is Cope’s fig. 18 ; 
3324 Cope’s fig. 25. 
3. A hinder neural, showing carina. Cope’s fig. 22. 
4. A hinder peripheral with a section (a) across it. 
greatest breadth about 20 mm.; thickness at the lateral border 4.5 mm., through the carina 
g-5mm. The carina is sharply defined and wider in front than behind. 
A portion of a hinder peripheral is present, being the original of Cope’s figs. 29 and 29a, 
and constituting, according to Cope, a portion of the same individual as those furnishing his 
figs. 27 and 30. Cope’s figure is inverted. This (fig. 334) bone has a height of 27 mm. in a 
direct line, and a maximum thickness of 7 mm. Its width can not be determined, as the bone 
has been broken near the descending sulcus. This sulcus, in contradistinction to those of the 
costals and neurals, is broad and deeply and irregularly imprest. Along the upper border of 
the bone runs what appears to be the longitudinal, or costo-marginal, sulcus. On the under 
