290 THEOPHILUS S. PAINTER 



equatorial plate views, while figure 21 is an anaphase stage. 

 Figures 22 to 24 show three cells in which six macro-chromosome 

 elements are present. In equatorial view (figs. 22 and 23) the 

 additional X-element appears either as quadripartite (fig. 22) 

 or as a large bivalent chromosome. An anaphase stage (fig. 24) 

 shows six macro-chromosomes at each pole of the cell. This 

 would indicate that the X-element divides equationally at this 

 time. 



It will be noted that, in all the equatorial views of several 

 division stages, a number of micro-chromosomes are seen. In 

 figure 19 there are clearly ten elements and a blurred mass, which 

 is part of the faintly staining network found in all spindles. In 

 figure 20 there are eleven micro-chromosomes, one of which 

 is larger than the rest. In figure 21 it is clear that eleven 

 micro-chromosomes are going to each spermatid. Figure 23 

 again shows eleven micro-chromosomes. 



From the foregoing description it will be seen that, in Anolis 

 carolinensis, we have a bipartite chromosome which goes undi- 

 vided to one pole of the cell in the first maturation division. Its 

 behavior is typical of a so-called sex-chromosome or X-chromo- 

 some, and has been so regarded by the author. Later in this 

 paper further evidence for this conclusion will be presented. 



It is interesting to note, further, that the chromosomes of 

 Anolis behave in a way typical for insects and other invertebrates. 

 The tetrads are formed and divide in the typical invertebrate 

 manner, and the second spermatocyte division does not show any 

 fusion, or so-called 'double reduction,' such as has been described 

 for birds and some mammals. 



The transformation of the spermatids into mature sperm has 

 been followed out, but no description of it will be given here. 

 Giant sperm are occasionally found in Anolis and so-called 

 'syncytial masses' are common. These will be treated in a later 

 section of this paper. 



