Vol. X] VON GELDERN—SKIN OF ANOUS CAROLINENSIS 103 



It seems likely, however, that the pigment granules vary consid- 

 erably in the intensity of their color as has already been stated. 

 This conclusion is reached not only from a study of the pigment 

 granules in the melanophores but also from their effect on the 

 color of the skin. There is little doubt that a condensed mass of 

 pigment will produce a darker brown than more scattered pigment, 

 but the former will always be brown and can never be black or 

 brick-red. 



If this be true, then the melanophores producing the post- 

 orbital black patch must contain black pigment granules and 

 those producing the brick-red stripe must contain reddish-brown 

 granules. Furthermore, it is possible that an individual scale may 

 contain melanophores of two or more kinds of pigment content 

 and that these may act independently of one another. This is 

 suggested by the microscopic appearance as well as the appearance 

 of either a brick-red, brown, or black state in the scales of the mid- 

 dorsal and the post-orbital stripes. Undoubtedly the amount of 

 pigment present plays an important role, but many of these differ- 

 ences cannot be satisfactorily explained. Partial distal migration 

 may be responsible for a lighter brown color than maximal distal 

 migration, but only up to a certain point. Any distal migration 

 beyond this is not associated with a still lighter brown state but 

 with a slaty or greenish-gray color. 



The Connective Tissue Layer. — Lyijjg beneath the leucophore 

 layer, running into the concavity of the scale for a variable distance 

 but approaching more closely the epidermis at the edges of the 

 scale, is a fairly dense layer of white, fibrous connective tissue 

 (Figs. 8, lo, II, 12 and 13). The fibres appear to run parallel but 

 on closer inspection many vertical and oblique ones may be noted. 

 The vertical fibres may be traced as they ascend among the cells 

 of the leucophore layer where they break up into small fibril 

 bundles which form a network beneath the epidermis. This layer 

 takes on a bright pink color with eosin and contains many deeply 

 staining stellate and spindle shaped nuclei. It is fairly vascular 

 and nerves may be seen traversing it. Below the concavity of the 

 scale are present fat corpuscles and large blood vessels (Figs. 11, 

 12 and 13). Beneath the dense connective tissue separating the 

 skin from the underlying skeletal muscles, there is present a loose 

 areolar connective tissue. Fine free pigment granules forming a 

 fine line between the denser connective tissue and the looser 



