296 THEOPHILUS S. PAINTER 



Spermatogenesis of Uta ornata 



The study of the spermatogenesis of this form has been carried 

 out sufficiently to give the chromosome complex and the behavior 

 of the sex-chromosome. 



Spermatogonial divisions (text fig. 2, A and B) show the pres- 

 ence of twelve macro-chromosomes and from fifteen to eighteen 

 micro-chromosomes. Among the macro-chromosomes we dis- 

 tinguish a large pair, labeled 'a/ a small pair, 'b,' and the 'c' 







.^ ^ •% 



I 



E 



Text figure 2 Uta ornata. A and B. Dividing spermatogonia. C. Equa- 

 torial plate view of a dividing first spermatocyte. D and E. Equatorial plate 

 view of dividing second spermatocytes. 



pair as found in the other lizards of the family Iguanidae (text 

 fig. 2, A). The 'b' chromosomes are relatively large in this 

 species. 



The first maturation spindles show six macro-chromosomes and 

 about eight or nine micro-chromosomes (text fig. 2, C). In side 

 views of the spindles I have not observed the early migration of 

 an X-element to one pole. However, the secondary spermato- 

 cytes contain five (text fig. 2, D) and six (text fig. 2, E) macro- 

 chromosomes, the extra element being large and represents, 

 no doubt, the X-chromosome. Hence it is very probable that 

 a sex-chromosome is present in Uta ornata and that it behaves 

 like this element does in Anolis. 



