54. GOPHERUS 987 



movably 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 supracaudal plate. 



Of the three known species one occurs within our limits. 

 The genus is but doubtfully distinct from Testudo. 



228. Gopherus agassizii (Cooper) 



Desert Tortoise 



Plates 125, 126, and 127 



Xerobates agassizii Cooper, Proc. Cal. Acad. Sci., Vol. 2, 1863, p. 120 



(type locality, Mountains of California near Fort Mojave); 



Cooper, Proc. Cal. Acad. Sci., Vol. IV, 1870, p. 67; True, Proc. 



U. S. Nat. Mus., Vol. 4, 1881, p. 437; True, Bull. U. S. Nat. Mus., 



No. 24, 1883, p. 38. 

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



156; DiTMARS, Reptile Book, 1907, p. 69, pi. XXIV; Siebenrock, 



Zool. Jahrb., Suppl. 10, Heft 3, 1909, p. 517; Camp, Univ. Cal. 



Publ. Zool., Vol. 12, No. 17, 1916, p. 512; Grinnell & Camp, Univ. 



Cal. Publ. Zool., Vol. 17, No. 10, 1917, p. 199; Cowles, Journ. 



Entomol. & Zool., Pomona College, Vol. XII, No. 3, 1920, p. 64; 



Terron, Mem. y Rev. Soc. Cient. Antonio Alzate, Vol. 39, 1921, 



p. 165. 

 Gopherus agassizii Stejneger, N. Amer. Fauna, No. 7, 1893, p. 161; 



Van Denburgh, Occas. Papers Cal. Acad. Sci., V, 1897, p. 35; 



Mo Lain, Critical Notes, 1899, p. 2; Mebk, Field Columbian Mus., 



Zool. Series, Vol. 7, No. I, p. 3; Van Denburgh & Slevin, Proc. 



Cal. Acad. Sci., Ser. 4, Vol. 3, 1913, p. 397; Stejneger & Barbour, 



Check List N. Amer. Amph. Rept., 1917, p. 121; Van Denburgh & 



Slevin, Proc. Cal. Acad. Sci., Ser. Ill, Vol. XI, 1921, p. 29. 



Description. — Shell broad and deep, often flattened 

 above, its margin serrate all around, except in worn speci- 



