53 



This is the first conclusive report of parthenogenesis in this 

 genus. Museum specimens of _C. exsanguis , C. neomexicanus , C. tessel- 

 atus , _C. uniparens and C. velox collected at all times of the year were 

 examined, and all were found to be females. A genetic basis for this 

 phenomenon is suggested rather than differential utilization of habitats 

 and/or activity periods by males. 



I'^S. — . 1966. The sex of hatchlings of five apparently unisexual 

 species of whiptail lizards (Cnemidophorus , Teiidae). AMERICAN MID- 

 LAND NATURALIST 76: 369-378. 



The ecological and genetic hypotheses regarding parthenogenesis 

 are reviewed as they might apply to the genus Cnemidophorus . Eggs ob- 

 tained from wild-caught individuals of ^ presumed parthenogenetic spe- 

 cies ( exsanguis , perplexus (= neomexicanus ), tesselatus and velox ) pro- 

 duced only female progeny. Hatching success was low; this is postulated 

 as a reason for the spotty distribution and/or local extinction of popu- 

 lations of these species, but is also at least partly due to laboratory 

 procedures. The habitat exclusion and inequality of numbers of bisexual 

 and unisexual Cnemidophorus where they are geographically sympatric (i. 

 e. sexlineatus and tesselatus in Colorado) is briefly discussed. 



lif.if., _. 1967. Skin grafting in the bisexual Teiid lizard Cnemido - 

 phorus sexlineatus and in the unisexual C. tesselatus . JOURNAL OF 

 EXPERIMENTAL ZOOLOGY 166(1): 137-1^9. 



Pattern classes of _C. tesselatus from Colorado (A, B, and C) and 

 New Mexico (E) were studied, as well as C. neomexicanus from New Mexico 

 and _C. sexlineatus viridis and _C. tigris septentrionalis from Colorado. 

 Procedures were tested and rejection criteria were established. Homo- 

 grafts between individuals of isolated populations of _C. tesselatus are 

 accepted. This species will reject skin grafts from other species of 

 Cnemidophorus . Pattern classes A and 5 from east of the Rocky Mountains 

 are histocompatible. One individual from pattern class C rejects grafts 

 from class A and B individuals but can successfully donate to them as 

 well as to individuals of class E from northern New Mexico west of the 

 Continental Divide. Class E individuals can successfully donate to the 

 other three classes. Northern class E individuals reject grafts from 

 classes A and B but accepts class C grafts. These skin graft reactions 

 are correlated with the triploid nature of pattern classes A and B and 

 the diploid nature of C and E. The lack of uniform results and the 

 small samples used does not preclude the possibility of incompatible 

 clones within the geographic areas of individual pattern classes. 



145. — . 1968. Taxonomic problems in parthenogenetic vertebrates. 



