1922] Schmidt, Amphibians and Reptiles of Lower California 609 



by Van Denburgh, published in 1895, with numerous subsequent papers 

 by the same author, and especially the recent papers by Van Denburgh 

 and Slevin on the unrivalled Lower Calif ornian collections of the Cali- 

 fornia Academy of Sciences, form an excellent introduction to this fauna, 

 greatly facilitating systematic work, and I have had constant reference 

 to them in the course of the work on the present paper. Several points 

 have been cleared up by correspondence with Dr. Van Denburgh and by 

 reference to specimens received in exchange from the California 

 Academy of Sciences. In order to make clear the cases in which I have 

 differed from these authors, and especially to corroborate or place 

 definitively in the synonymy the species proposed by Dickerson, I have 

 given a new ''complete list" of the species recognized. As I have been 

 compelled to make preliminary revisions of several genera concerned, 

 I have included keys to the peninsular species of the remaining genera 

 and have prefixed artificial keys to the genera, in the hope of increasing 

 the usefulness of the paper to amateurs and especially to students of other 

 departments of science who may have occasion or opportunity to deal 

 with the herpetological fauna of Lower California. Too large a pro- 

 portion of the species in the Lower Californian fauna are unrepresented 

 in the material available to me for study at the present time to warrant 

 a more complete account. I have not included the geographically 

 unrelated Tres Marias Islands off the west coast of Mexico, but have 

 included the reptiles found in the Revilla Gigedo Islands, following the 

 limits of the ' Check List of North American Amphibians and Reptiles,' 

 Stejneger and Barbour, 1917. This extremely useful list has been con- 

 stantly at hand. As it establishes the nomenclature of the North Ameri- 

 can species more satisfactorily than any other authority, I have 

 included a reference to it under each species and, in all cases in which I 

 have not followed its nomenclature, I have quoted the authority made 

 use of or have stated nry own reasons for such divergence. 



The recent monograph of Lower California by Dr. Edward W. 

 Nelson, Chief of the Bureau of Biological Survey, U. S. Dept. of Agri- 

 culture (1921, Mem. Nat, Acad. Sci., XVI, pp. 1-194, Pis. i-xxxv) 

 describes the plrysical conditions of the peninsula of Lower California, 

 illustrates the character of every part of the peninsula in a fine series of 

 plates, and gives an account of the distribution of its plant and animal 

 life. Unfortunately, no complete account of the amphibians and reptiles 

 subsequent to that of Van Denburgh in 1895 was available for the discus- 

 sion of the distribution of the reptile fauna in. Dr. Nelson's paper, and I 

 have no hesitation, therefore, in presenting a new account of the distribu- 



