and _C. neomexicanus (map presented), and eastern range margins of C. 

 tigris gracilis appear to have been influenced by various lacustrine 

 barriers. Records for C. neomexicanus in the Jornada del Muerto, but 

 not in the Elephant Butte Basin, support contentions that the ancestral 

 Rio Grande once flowed through the former; Quaternary basalt flows in 

 the middle Jornada are believed to have diverted it westward through the 

 Elephant Butte Gap. 



9. — . and R. G. Webb. 1963. New records for reptiles from Chihua- 

 hua, Mexico, with comments on sympatry between two species of Cnemido - 

 phorus . SOUTHWESTERN NATURALIST 8(1): 50-51. 



Evidence suggesting possible gene exchange between C. exsanguis 

 and _C. septemvittatus scalaris is discussed. 



10. Ayala, S. C. and 3. J. Schall. 1977. Apparent absence of blood 

 parasites in southwestern Texas Cnemidophorus . SOUTHWESTERN NAT- 

 URALIST 22(1): 13^^-135. 



Species examined were exsanguis , gularis, inornatus, tesselatus 

 and tigris . It is suggested that hemoprotozoan diseases are not impor- 

 tant population regulating factors here as they are in natural popula- 

 tions elsewhere. 



11. Ballinger, R. E. and D. R. Clark, 3r. 1973. Energy content of 

 lizard eggs and the measurement of reproductive effort. JOURNAL OF 

 HERPETOLOGY 7(2): 129-132. 



Values of caloric and water content for eggs of Cnemidophorus 

 gularis and _C. sexlineatus are given. The determination of reproduc- 

 tive effort is briefly discussed. 



12. — . and C. O. McKinney. 1968. Occurrence of a patternless morph 

 of Cnemidophorus . HERPETOLOGICA 2't(3): 26^^-265. 



A photograph and description of Cnemidophorus tigris marmoratus 

 from Crane County, Texas, is given. 



13. — , J. W. Nietfeldt and 3. 3. Krupa. 1979. An experimental anal- 

 ysis of the role of the tail in attaining high running speed in Cnemido - 

 phorus sexlineatus (Reptilia: Squamata: Lacertilia). HERP. 35: 114-116. 



