18. TESTUDINIDJE 



Marginals twelve on each side and a small nuchal. Plastron 

 large, rounded, completely closing the shell, hinged between 

 pectorals and abdominals} anal, femoral and humeral plates 

 largest; gulars smallest. Axillary and inguinal plates absent. 

 Head rather large, covered above with smooth skin. Limbs 

 well developed, anterior with five, posterior with four, 

 clawed digits which are little if at all webbed. Tail rather 

 short and slender. 



The general color and markings are quite variable. The 

 carapace usually is brown, olive, or yellowish, marked with 

 yellow rays which radiate from the center of growth of each 

 plate. In some specimens these light rays are few or obso- 

 lete. The plastron is similarly marked. The head, neck 

 and limbs are brown or olive with yellowish or orange mark- 

 ings. 



Length of carapace 121 



Length of plastron 126 



Width of carapace 105 



Width of plastron 78 



Distribution. — This turtle ranges from Indiana, Illinois 

 and the Mississippi Valley west to the Rocky Mountains and 

 southern Arizona. 



In Arizona it has been collected near Fort Lowell and 

 La Osa, Pima County, and Fairbank, and Ramsey Canyon, 

 Huachuca Mountains, Cochise County. The National Mu- 

 seum has it from the Graham Mountains at 4,600 feet. 



Genus 54. Gopherus 



Gofherus Rafinesque, Atlantic Journal, Vol. 1, No. 2, 1832, p. 64 



(type, folyfhemus). 

 Xerobates Agassiz, Contr. Nat. Hist. U. S., Vol. 1, 1857, p. 446 (types, 



folyfhemus and berUndieri) . 



The shell is very broad and high. The plastron is im- 



