REPTILES OF THE PACIFIC COAST. 35 



found in the San Francisco markets. In each instance 

 the market-men told me that the turtle had been sent in 

 with fish from the San Joaquin River near Stockton, 

 California, but, when questioned, could not state pos- 

 itively that the lot had not come from Oregon or Wash- 

 ington. 



Genus 3. GOPHERUS. 



Xerobates, AGASSIZ, Coutr. Nat. Hist. U. S., I, 1857, p. 446 (types 

 polyphemus and berlandieri) . 



The shell is very broad and high. The plastron is 

 immovably united to the carapace by a broad bridge. 

 There is a ridge along the middle of the alveolar surface 

 of each side of the upper jaw parallel to the cutting 

 edge, except in front, where there is a longitudinal ridge 

 at the symphysis. The internal openings of the nostrils 

 are between the eyes. The limbs are club-shaped, the 

 fore limbs flattened, without webs. The skin on top of 

 the head is divided into scales. There is but one supra- 

 caudal plate. 



3. Gopherus agassizii (Cooper). DESERT TORTOISE. 



Xerobates agassizii, COOPER, Proc. Cal. Ac. Sci., II, 1863, p. 120 

 (type locality Mountains of California near Fort Mojave); 

 TRUE, Proc. U. S. Nat. Mus., IV, 1881, p. 437. 



Testudo agassizii, BOULENGER, Cat. Chelonians Brit. Mus., 1889, p. 

 ' 156. 



Gopherus agassizii, STEJNEGER, N. A. Fauna, No. 7, 1893, p. 161. 



Description. Shell broad and deep, often flattened 

 above, its margin serrate all around, except in worn 

 specimens, and usually more or less rolled upward over 

 limbs. Growth-center of each plate smooth, but usually 

 surrounded by beautifully ribbed shell. Vertebrals five, 

 last largest and widest. Costals four, first longest, sec- 

 ond and third about equally high, last smallest. Nuchal 

 not much narrower than long. Marginals eleven and a 

 half on each side, last pair being united to form a 



