The collection was made during 3uly and August in the vicinity of 

 Alamogordo, New Mexico, and Tucson, Arizona, respectively. The habi- 

 tats, geology and climate of the areas is described, as well as speci- 

 fic collecting sites. Cnemidophorus gularis (= exsanguis ) is common at 

 Alamogordo in the lower part of canyons and in stony arroyos on allu- 

 vial slopes. It (= flagellicaudus and/or sonorae ) occurs in the same 

 habitats at Tucson, as well as along the Santa Cruz river in willow- 

 poplar associations. Other habitat and morphological details are 

 given. Beetles and ants make up the bulk of the stomach contents. 

 Cnemidophorus melanostethus (= tigris + possibly tesselatus ) is very 

 common in the creosotebush association of alluvial slopes near Alamo- 

 gordo and is exclusive to it there. It (= tigris ) occurs in greasewood 

 plains and creosotebush of mesa arroyos near Tucson. Behavior and mor- 

 phology are discussed. _C. sexlineatus (= inornatus ) occurs in the mes- 

 quite and Atriplex associations and on the White Sands near Alamogordo. 

 Ants, grasshoppers and spiders are eaten. Morphology is described. 



196. Saxon, 3. G. 1968. Sexual behavior of a male Checkered Whiptail 

 lizard, Cnemidophorus tesselatus . SOUTHWESTERN NATURALIST 13(^): 



The specimen was collected 1 mile east of Presidio, Texas, in the 

 Rio Grande valley. Cnemidophorus tigris was sympatric. Sexual behavior 

 between the male and a female tesselatus is described. Motile sperm 

 were produced by the male but none were present in the female and she 

 never became gravid. 



197. — . 1970. The biology of the lizard, Cnemidophorus tesselatus , 

 and effects of pesticides upon the population in the Presidio Basin, 

 Texas. PH.D. DISSERTATION, TEXAS A & M UNIVERSITY. 90 p. 



The Presidio Basin is limited to the floodplain of the Rio 

 Grande. Its soils, vegetation and agriculture are characterized. 

 Black and white photographs of the study areas and of _C. tesselatus 

 (juvenile-subadult-adult) are provided. Cnemidophorus tesselatus is 

 mostly confined to the Basin in this area. It occurs in isolated po- 

 pulations but not only in rocky areas— it is also found in backyards 

 and abandoned lots in the town of Presidio, and on levee and farm 

 roads. It is associated with disturbed areas where it is found on 

 surrounding desert mesas. Daily activity is confined between 9 a.m. 

 and 3 p.m.; soil and air temperatures at the beginning of activity are 

 32 and 30°C, respectively. Cloacal temperatures of active lizards ave- 

 rage 39.5°C. Gravid lizards have apparently restricted activities. 

 Domestic cats are by far the most important predator, with snakes next. 

 The activity season extends from March to November with the bulk occur- 

 ring from mid-May to mid-August. Soil temperature is the critical fac- 

 tor for activity. Hatchlings appear at the beginning of July and grow 

 to subadult size (50-69 mm) before entering hibernation. Lizards rare- 



