1913] Atsatt: Reptiles of tin San Jacinto Area 45 



CONCLUSIONS 



In the study of this collection of reptiles from the San Jacinto 

 area I find a fairly definite relation of their distribution to life zones. 

 In the Transition zone, which is the highest one in which reptiles were 

 found, both the species and individuals are few in number. The 

 Transition zone in general runs along the tops of the ridges, being 

 superseded by the Boreal only on the highest peaks. Parts of the 

 Transition are isolated from each other and still more so from the 

 Transition areas of other mountains of southern California. How- 

 ever, the two species Sceloporus graciosus and Lampropeltis pyrrho- 

 melaena multicincta, which are characteristic of the Transition zone 

 only, are found also in the Transition area of the San Bernardino 

 mountains about twenty miles to the north across a depression of 5000 

 feet between the two zones. 



The Souoran zones, both Upper and Lower, encircle this area. On 

 the northeastern and eastern sides of San Jacinto Peak the Upper 

 Sonoran is very restricted in area because of the great steepness of 

 the ridges, but on the western and the southern sides it spreads out 

 to the coastal valley and the Santa Rosa mountains. It really forms 

 the bulk of the actual area covered in collecting and it may be because 

 of that reason that the number of individuals seems largest in Upper 

 Sonoran. The Lower Sonoran occurs mainly pushing in from the 

 desert through the canons on the eastern side and running up through 

 San Gorgonio Pass, but appears also in "islands" on the western 

 base of the San Jacinto area. In the Lower Sonoran we find the 

 greatest representation of species and a large number of individuals. 



The relative distribution in these zones is detailed in Table I. 

 Where gaps resulting from insufficient representation in the collec- 

 tion have occurred I have filled in with the distribution as recorded 

 in the entire range of the various species by other writers, principally 

 Van Denburgh (1897). Species occurring occasionally, but probably 

 not in any considerable numbers, are placed in parentheses. 



There are two marked faunas in the San Jacinto area, one in 

 extremely arid country, known as the Colorado desert fauna, and the 

 other in a semi-humid region, known as a part of the Pacific coast 

 fauna, namely, the San Diegan fauna. While, roughly speaking, 

 one of the faunas lies to the east and north of, and the other to the 

 west and south of the main ridge of peaks, there are certain localities, 



