9 8 



FOSSIL TURTLES OK NORTH AMERICA. 



The width of the base is 150 mm. The bridge is 167 mm. wide The length of the hinder lobe 



was approximately 100 mm.; the width at the base is 165 mm. It narrows rather rapidly 



backward, so that at the femoro-anal sulcus the width is 104 mm. 



There are present large mesoplastra, the boundaries of which can be pretty satisfactorily 



determined. These are about 35 mm. wide at the midline, but thev expand to about 85 mm. 



at the peripherals. 



The median longitudinal sulcus runs a very irregular course, and across the temorals it 



can not be distinguisht with certainty. The humerals occupy 70 mm. of the midline; the 



pectorals, about 90 mm.; the abdominals, about 35 mm.; the 

 femorals, about 52mm. The femoro-anal sulcus runs far forward 

 from its starting point on the border of the plastron. Probably on 

 account of weathering, the sculpture of the carapace is nearly 

 obliterated, appearing only in a few spots. On the plastron it is 

 more distinct. It appears to have resembled that of T. insdiens 

 and consists of narrow and low ridges and tubercles. Some traces 

 are observed ot the ridges due to the growth of the scutes. 



This species differs from T. insiliens in having the nuchal 



less deeply excavated, in having a median depression along the back, and in having the hinder 



lobe of the plastron more rapidly reduced in width backward. In T. insiliens the bridges are 



considerably wider than the base ot the hinder lobe. 



Genus CHARITEMYS nov. 



A genus of Baenida?. So far as known like Thescelus, but with the axillary buttresses 

 ascending to near the neural borders of the first costals. Inguinal buttresses probably ascend- 

 ing on inner surfaces of the fifth and sixth costals, but not to so great a height as did the axillary 

 buttresses. 



Type: Charttemys captans Ha}'. 



Charitemys captans sp. nov. 

 Text-figs. 93-95. 



The type of the present species is No. 6098 of the American Museum of Natural His- 

 tory. It forms a part of the Cope collection of fossil reptiles and was collected in 1876, by 

 Messrs. Sternberg and Isaac, in the Judith River deposits of Montana. There are present 

 considerable parts of both the carapace and the plastron, but unfortunately important parts 

 are missing. 



In size this species appears to have been somewhat smaller than the type of Thescelus 

 insiliens, judging from the plastral bones, but of the same size, if we judge from the widths of 

 6 costal bones. 



Of neurals there are portions of only two. One of these, probably the eighth, has a width 

 of 44 mm. Its length can not be determined, what is regarded as the posterior end being 

 broken away. On the supposed anterior end is a rounded carina. The broader end is crost 

 by a sulcus, probably that between the fourth and the fifth vertebral scutes. On the under side 

 are three impressions for three neural spines. The other neural is only 30 mm. wide. It 

 probably belonged near the beginning ot the series. 



Of the costals there are present the proximal end of the first of the left side, the right 

 second, third, and sixth, and the left fourth, fifth, sixth, and seventh. Fig. 93 represents the 

 second and third right costals; fig. 94, the fourth to the seventh of the left side. Of the latter 

 three, mote or less of the distal ends are missing. The supposed first presents difficulties. 

 On the upper surface are found portions of the first and second scute areas and ot the first 

 costal area. The area of the first vertebral scute on this costal is only 16 mm. wide. The 

 whole width of this scute could hardly have exceeded 65 mm. On the lower side is a large tri- 

 angular articular scar for the axillary buttress of the plastron. This approacht within 21 

 mm. of the neural border of the costal. Between the scar and the neural border is a sharp 

 ridge from which appears to have been broken the rib-head of the costal. This was much 

 slenderer than those of the succeeding costals. The slenderness of this rib-head was hardly to 



