Vol. X] VON GELDERN—SKIN OF ANOLIS CAROLINENSIS 95 



racy. These cells were not described by Carlton, but Keller has 

 described similar cells for the chameleon and named them zan- 

 thophores, and Pouchet also described similar cells for the chame- 

 leon and believed that they contained fat droplets of 2.5 microns. 

 He believed these cells to be analogous to the yellow cells of batra- 

 chians and that they possessed the power of contractility. Keller 

 also believed that they could expand or contract for he found them 

 varying markedly in size. Doctor Irving Hardesty suggests that 

 these cells secrete or control the accumulation of the oil droplet 

 layer described above. 



If Keller and Pouchet be correct in their assumption that these 

 large clear cells may expand, one might reason that during this 

 state they practically fill the entire space between the epidermis 

 and the underlying layer and force the yellow droplet layer towards 

 the periphery of the scale so that it no longer influences the color 

 states. 



For reasons which will be taken up later, I believe that the 

 mechanism is not quite as Keller would have one believe, although 

 undoubtedly these cells are more nimierous and almost replace 

 the oil droplet layer in the white scales of the mid-dorsal stripe. 

 If these large, spherical cells in Anolis are the zanthophores of 

 Keller, and they resemble very closely those he figures and de- 

 scribes, Carlton is wrong in stating that these cells do not exist 

 in Anolis. 



The Leitcophore or Guanophore Layefr— The layer lying just be- 

 neath the layer of oil droplets presents very marked differences 

 from any of the structures previously described. In vertically 

 sectioned scales, stained with haematoxylin and eosin, it is seen 

 that this layer is thicker near the center of the scale and then 

 gradually thins out until it disappears at the periphery. The layer 

 forms then an inverted cup which thins out at the edges and fits 

 into the hollow epidermal scale but does not come in immediate 

 contact with it because of the intervening oil droplet layer. It is 

 present in all the scales of the skin including those of the ventral 

 aspect of the body (Figs. 8, 10, 11, 12, 13, 14 and 17). By reflected 

 light it appears as a homogeneous bluish- white band (Fig. 10 B), 

 and this appearance is not lost in those sections fixed in the fluid 

 mentioned and stained with haematoxylin and eosin. Bits of the 

 layer may be found isolated in the deeper fibrous layer, recogniz- 

 able by the bluish-white color. 



