33& 



FOSSIL TURTLES OF NORTH AMERICA. 



mm.; its width 128 mm. The length then has a high ratio to the width, being 75 per cent, 

 thereof. The lateral border runs nearly straight to a point some distance in front of the hyo- 

 epiplastral suture, then rounds rapidly to the lip. The lip is 53 mm. wide. It projects little 

 and is furnisht with a right and a left lateral tooth and 2 closely placed median teeth. Between 

 the lateral tooth and the midline the upper surface of this lip is considerably excavated. The 

 thickening of the epiplastrals on the upper surface (fig. 444) extends backward 30 mm. The 

 greatest thickness of these bones is 12 mm. The median space between these thickenings on 

 the upper surface is somewhat excavated. The free borders of the lobe are acute nearly to 

 the lip. The beveled surface on the upper side of the epiplastrals has a width of only 12 mm. 

 at the hyoepiplastral suture. The entoplastron is 50 mm. long and 60 mm. wide. The bridge 

 has a width of 137 mm. The hinder lobe is 98 mm. long and 143 mm. wide at the base. The 

 length of the lobe equals therefore about 69 per cent, of the width. There is a rather broad 

 notch at the rear of the lobe. Its width is about 12 mm. The beveled surface on the upper 



442. 



Figs. 442 AND 443. Echmatemys naomi. Carapace and plastron of type. X J- 

 442. Carapace. 443. Plastron. 



side of this lobe, at the hyoxiphiplastral suture, is 28 mm. wide. The bones here have a thick- 

 ness of 13 mm. 



The anterior buttresses appear to arise but a short distance within the free border of the 

 base of the anterior lobe. The posterior buttresses reach inward from the border of the hinder 

 lobe half-way to the midline. 



The gulars are 47 mm. long; the humerals, 31 mm.; the pectorals, 60 mm.; the abdomi- 

 nals, 86 mm.; the femoials, 53 mm.; the anals, 38 mm. The humero-pectoral sulcus cuts 

 across the hinder end of the entoplastron. The median longitudinal sulcus runs a very irregular 

 course. 



The axillary scute is large and its hinder end joins the fifth marginal for a distance of 13 

 mm. Hie inguinal scute is also large, its outer boundary being 38 mm. long, and lacking 12 

 mm. of reaching the sixth marginal. 



From all other described species this differs in the depth of the channels in which run most 

 of the carapacial sulci. From E. stevensoniana it differs also in having broader neurals and in 

 its broader, urn-shaped, vertebral scutes. These scutes likewise distinguish it from E. shaugh- 



