36 

 gynogenesis, hybridogenesis, or spermatozoa in any way whatsoever. 



97. Harris, A. H. 1965. The origin of the grassland amphibian, rep- 

 tilian, and mammalian faunas of the San Juan-Chaco River drainage. 

 PH.D. DISSERTATION, UNIVERSITY OF NEW MEXICO. 160 p. 



Grassland habitat of the present type was absent during the last 

 major Pleistocene pluvial. Animals associated with it had to invade 

 through habitat corridors to the northwest or from relatively low-lying 

 areas along the Continental Divide to the southeast. Climatic and vege- 

 tational changes of the area since the last major pluvial (Wisconsin) 

 are discussed in detail. Cnemidophorus tigris septentrionalis is found 

 along washes and in rocky areas of pinyon-juniper habitats in the study 

 area. _C. tigris marmoratus is found in the Rio Grande basin to the east 

 and southeast, and the two subspecies are separated by the Continental 

 Divide. Previous contact was impossible and the former invaded from the 

 north and northwest. Cnemidophorus inornatus is rare in the study area; 

 it occurs in a few localities bordering Gallegos Canyon and at the bor- 

 ders of sagebrush and grassland habitats. Only clinal variation exists 

 between this isolated population and those in the Rio Grande basin, 

 therefore they were probably contiguous at one time. The present popu- 

 lation invaded during the post-pluvial period, when the climate was most 

 likely warm and wet rather than warm and dry, and may have been isolated 

 for a maximum of ^000 years. 



98. — . and 3. S. Findley. 1964. Pleistocene-Recent fauna of the 

 Isleta caves, Bernalillo County, New Mexico. AMER. J. SCI. 262: 114- 

 120. 



The fauna includes Cnemidophorus perplexus . No age is given for 

 the material, nor is it clear which of the currently recognized species 

 is referred to. 



99. Hayward, C. L., D. E. Beck and W. W. Tanner. 1958. Zoology of 

 the Upper Colorado River Basin. I. The biotic communities. BRIGHAM 

 YOUNG UNIVERSITY SCIENCE BULLETIN, BIOLOGY SERIES 1(3): 1-74. 



Cnemidophorus tigris septentrionalis is common in greasewood, 

 Cottonwood, tamarisk and willow floodplain habitats with sandy to clay 

 soils in southeastern Utah. It is common over a wider range from bar- 

 ren desert washes to pinyon-juniper habitats with gravelly to rocky 

 soils at Arches National Monument, where _C. velox overlaps slightly 

 with it, extending throughout the elevational range of pinyon-juniper 

 habitat. There are local habitat variations for both species apparent 

 throughout the region. _C. velox is restricted to the Colorado Plateau 

 Province; _C. tigris septentrionalis occurs in that plus the Uinta Moun- 



