Vol. XI] VAN DENBURCH-SLEVIN—NEW SPECIES OF REPTILES 97 



Guarclia Island seven miles north of Pond Island, Gulf of Cali- 

 fornia, Mexico, May 3, 1921. 



Cnemidophorus bacatus, new species. 



Diagnosis. — Structurally similar to C. tcsscllatus, but color- 

 ation very distinct. Upper surfaces brown or dark gray, 

 shading to blackish on the hind limbs, with small, discrete, more 

 or less equidistant, sometimes black-edged whitish spots or 

 ocelli on the sides and back of body, hind limbs and base of tail. 



All lower surfaces black. No longitudinal markings at any 

 age. Femoral pores 16 to 20. 



Type. — California Academy of Sciences No. 49152 ; collected 

 by Joseph R. Slevin on San Pedro Nolasco Island, Gulf of Cali- 

 fornia, Mexico, April 17, 1921. 



Cnemidophorus canus, new species. 



Diagnosis. — Similar to C. martyris but much paler and with 

 black suffusion restricted to the central subcaudal scale rows 

 and the distal part of the tail. Upper surfaces light gray or 

 brown with very indistinct fine dark gray reticulations on the 

 body and hind limbs. No longitudinal markings. Lower sur- 

 faces of head, body and limbs bluish gray, often with a few 

 minute black dots on the throat and a little black about the 

 edges of the large plates on the chest, belly and limbs. Femoral 

 pores 16 to 20. 



Type. — California Academy of Sciences No. 49153; col- 

 lected by Joseph R. Slevin on Sal Si Puedes Island, Gulf of 

 California, Mexico, May 9, 1921. 



Cnemidophorus dickersonae, new species. 



Diagnosis. — A member of the C. tessellatns group somewhat 

 intermediate in coloration between C. t. stejncgeri and C. mcl- 

 anostethiis, having the yellowish brown dorsal ground color of 

 the former and black gular and thoracic suffusion of the 

 latter. 



Dorsal longitudinal markings less evident than in either, 

 and sides dark brown or black with whitish spots or transverse 

 bars. It thus resembles C. cslebanensis, but the pattern is quite 

 different. 



