276 FOSSIL TURTLES OF NORTH AMERICA. 
except that they, like the other bones of the carapace, appear to be somewhat thinner. The 
vertebral scutes are perhaps relatively a little wider than in B. wyomingensis. There are 3 
broad dorsal carina—a median and two lateral. The median may be traced farther forward 
than in B. wyomingensis, as far forward as the front of the third neural. The lateral carine 
run just outside of the vertebral scutes. They are of moderate height posteriorly; on the 
Fics. 346 AND 347.—Baptemys tricartnata. ie and plastron of type. 4. 
346. Portion of carapace. c. p.1, first costal plate; 7.1, 1. , first and eighth neurals. 
47. Plastron and portion of carapace. 
anterior half of the carapace they may be traced to the first costal; but on the three anterior 
costals they form very low ridges. 
Fig. 347 represents the lastron. The total leneth is 285 mm. The anterior lobe is broad 
347 rep P : ig 5 : ) 
enindea: and slightly notcht in front. The length is g2 mm.; the width at the base, 148 mm. 
The entoplastron i Is larger than in B. wyominge nsis, being 65 mm. long and 75 mm. ae The 
349. 
Fics. 348 AND 349.—Baptemys tricarinata. Plastron and humerus of type. 4. 
348. Anterior lobe of plastron. 349- Right humerus. 
bridge is 93 mm. wide, relatively narrower than in the Bridger species. The hinder lobe is 
105 mm. long and 111 mm. wide at the base. The sides converge backward to a point. 
The panel areas are represented in fig. 347. No gulars are markt out; but there is a notch 
in the border of the epiplastron, as if for the crossing of the gulo-humeral sulcus. There are 
on each bridge 3 inframarginals like those of most specimens of B. wyomuingensts. 
ay $i 
