156 



3. The 3'ellow (red in life) border to the anterior margins of the 

 costal and vertebral scutes or plates is wider in picta than in mar- 

 ginata. (Authority of Dr. Hay.) Of course in marginata^ these 

 borders do not form straight transverse stripes as in typical jpiGta. 



4. The plates of the carapace in marginata show concentric striae 

 or ridges (in our specimens) while in picta the scutes are smooth, 

 except in occasional specimens. 



Variations in scale arrangement. Our specimen No. S785g^ has 

 six vertebral plates in a row and five costals in regular arrangement. 

 No. 8785g^ has an extra trinangular plate between the fourth and 

 fifth vertebrals, on the left side, not in the middle. 



No. STSSg* has the third costal of the left side divided trans- 

 versely into two quadrilateral plates. The fourth costal in the left 

 side is triangular instead of quadrilateral. 



In No. 1073 there is a fifth costal on each side, triangular in shape. 

 The last vertebral plate is correspondingly modified to an octagonal 

 shape. 



The greater number of adults have rather sharp serrations or 

 points on the anterior margins of the carapace. There are also 

 serrations usually on the anterior and posterior borders of the plas- 

 tron. 



The vertebral line of red (yellow in formalin) is present in every 

 ease. It may be dim or present only on the posterior part of the 

 carapace, but part of it at least is always present. 



The Margined Turtle is found in places or situations similar to 

 those frequented by the Painted Turtles, and the food and economic 

 features are similar. It has been reported that this turtle is found 

 out of its winter quarters as late as December 22nd and in the spring 

 has been moving as early as the 31st of March. 



It is common in the swamps and ponds of the north-eastern por- 

 tion of Mississippi Valley where we have seen them in great numbers" 

 on logs and stones disporting themselves with just such habits as 

 are seen in the Painted Turtles in the eastern part of Pennsylvania. 



Unfortunately we have had examined in our laboratory only two 

 stomachs of the Margined Turtle collected in Pennsylvania, but we 

 have little doubt that the food of these turtles is practically the same 

 as that of the closely related Painted Turtle. Dr. Hay reports that 

 the food is probably insects, tadpoles and feeble and small animals. 



Species 14. Clemmys muhlenbergi (Schweigger). Muhlenberg's 



Turtle. 



This is know as Muhlenberg's Turtle from the fact that Schweigger 

 chose to name this reptile in honor of one of the early writers on 

 such subjects. It has also been called Muhlenberg's Tortoise, and 

 Terrapin and the Mud Turtle. While it lives in the mud, as do 



