APPENDIX F. REPTILES. 205 



Syn. — Phrynosoma cornutum, Gray, Sy.n. Rept. in Griff, Anim. Kingd. 



IX, 1831, 45. Holbr. N. Amer. Herp.II, 1842, 87. PL xi.— Girard 



in Stansbury's Expl. Val. Great Salt Lake, 1852, 360. PI. viii, fig. 



1—6. 

 Agama cornuta, Harl. Med. and Phys. Res. 1835, 141. Plate, figs. 1 



and 2. 

 Phrynosoma Harlani, "Wiegm. Herp. Mex. 1834, 54. — Dum. and 



Bibr. Erp. gen. IV, 1837, 314. 



Obs. — The color of this species has been well described by Dr. Hol- 

 brook. We may add that the ground-color above in some individuals 

 is of a variable shade of ferruginous red— a tint sometimes seen on the 

 inferior surface of the body. The belly is either uni color, or else spotted 

 as in P. orbiculare. Numerous specimens of this species were collected 

 during the exploration of Red river ; some on the prairie between Camps 

 2 and 3 ; others between Camps 6 and 7, and at Camp 7 also ; others 

 still on the south fork of Red river, and several other localities. 



II. CROTAPHYTUS, Holbr. 



Noticed for the first time during Major Long's expedition. The type of 

 this genus was briefly described by Say in the second volume of Long's 

 Narrative, and there called Agama collaris, in allusion to the very 

 striking feature of bearing a double black sub-crescentic band on the 

 sides of the neck. The genus Crotaphytus was first established by 

 Dr. Holbrook, and is characterized by the presence of small, polygonal 

 plates on the whole surface of the head. The odd occipital plate itself 

 is inconspicuous ; the auditive apertures are very broadly open. Teeth 

 are found on the jaws and palate. There is a fold of the skin under 

 the throat ; the head is large and sub-triangular ; the body covered with 

 minute scales ; and the tail very long and tapering. Femoral pores 

 present. 



This genus now includes four North American species ; three we 

 have lately described under the names of C, Wislizenii, from New 

 Mexico, C. Gambelii, from California, and C. dorsalis, from the desert 

 of Colorado ; the fourth is the following : 



