The Musk or Mud Turtles 



of the common mud turtle, being yellowish-brown, yellowish- 

 green or olive. The margins of the shields are narrowly bordered 

 with black. The plastron is yellow. 



The upper surface of the head is generally uniform olive, 

 while the sides of the head and neck are bright yellow. The eye 

 is bright yellow, with a horizontal bar of black through the 

 centre of the iris. 



Male specimens possess much longer tails than the females.* 



Dimensions. Length of Carapace 4! inches. 



Width of 3t 



Length of Plastron 4! 



Width of Front Lobe, 'at Hinge. . . 2 J 



" Rear ... 2^ 



Distribution. The range of this species is from Arkansas 

 (inclusive) through Texas and into Arizona. It probably in- 

 habits several of the rivers of northern Mexico. 



THE ARIZONA MUD TURTLE 

 Cinosternum benrici, (LeConte) 



This is a large species and might be described as inter- 

 mediate between the species of the genus already considered and 

 the Mexican and Central American species, with which the lobes 

 of the plastron are very wide and the hinges so elastic that the 

 shell closes as tightly as with the true box turtles (Cistudd), a 

 character clearly seen in the illustration of the following species 

 C. integrum. 



Colouration. The carapace is brownish-yellow; the plastron 

 pale yellow. Above, the head and neck are dull olive; both 

 are thickly sprinkled with yellow on the under surfaces. 



Dimensions. The species attains a length of five or six 

 inches. 



Distribution. Arizona and New Mexico. 



THE MEXICAN MUD TURTLE 

 Cinosternum integrum, (LeConte) 



Although this species does not occur in the United States, 

 it ranges well into the northern portion of Mexico. Its descrip- 

 tion is given as representing the type of the tropical species of 

 this genus. 



* A character to be noted with all the species. 



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