1022 



Schmidt , Amphibians and Reptiles of Lower California 



625 



While five of those are at present known only from the island, it seems 

 probable that they occur on the adjacent coast of Sonora. The appear- 

 ance of Micrurus euryxarithus is a striking evidence of the non-Californian 

 character of the Tiburon fauna. 



The two species of lizards known from San Pedro Martir Island, 

 (7a palmcri and Cnemidophorits martyris, are highly peculiar but the re- 

 lations of the latter with C. disparilis of Tiburon Island lead me to asso- 

 ciate this island with the Mexican mainland. 



Only two species, Uta nolascensis and Cnemidophorus bacatus, are 

 known from the island of San Pedro Nolasco. 



A large number of species confined to islands in the Gulf of California 

 are now known, the total (to January 1, 1922) being thirty-four, with 

 sixteen islands represented. As no less than fourteen of these are known to 

 me only from the preliminary diagnoses, I am unable to form definite 

 opinions as to their relations. The mere list, however, is instructive: 



Crotaph ytus d ickerson * 



" insularis 



Sauromalus hispidus 

 townsendi 

 varius 

 Callisaurus splendidus 



ventralis in usitatus 

 Sceloporus lineatulus 



monserratensis 

 Sator angustus 



" grandsevus 

 Uta palmeri 

 " squamata 

 " nolascensis 

 Cnemidophorus vandenburghi 

 celeripes 

 estebanensis 

 punctilinealis 



Cnemidophorus disparilis 

 " martyris 



" catalinensi 



" dickersonse 



canus 

 " bacatus 



Verticaria ceralbensis 

 espiritensis 

 sericea 

 cserulea 

 franciscensis 

 picta 

 Coluber barbouri 

 Lam propcltis cata linen sis 

 Crotalus tortugensis 

 " atrox elegans 



There are thirty species of lizards and only four snakes. Of the thirty 

 lizards, sixteen are teiids belonging to the two genera Cnemidophorus 

 and Verticaria. The ten insular Cnemidcphorus compare with five penin- 

 sular species, the six insular Verticarias with three on the peninsula. The 

 great majority of all of the species will certainly be found to be very 

 closely allied to the peninsular or Mexican forms from which they are 

 derived. In contrast to these stands a small number of very distinct 

 forms, such as the species of Sauromalus, the Sators, and possibly Verti- 

 caria ceralbensis. The latter group of species I believe to have been differ- 



