242 MAINE AGRICULTURAL EXPERIMENT STATION. I9I4. 



in the flattened cells of the corneum, they occupy that position 

 which would have been held by the nuclei, had they not degen- 

 erated. Instead of being oval groups as are those in the under 

 portions of the Malphigian layer, they he in short thin hnes, 

 which is to be expected, as these cells are greatly compressed. 

 Where these granules occur in the rete layer they tend to cluster 

 around the nuclei, and clearly indicate, by their arrangement, 

 the changes in form which have accompanied these cells in their 

 migration toward the surface. 



In the corium, and less frequently in the rete layer, what 

 appear to be dense masses of dark colored pigment granules are 

 found. These are in reality definite cellular bodies, the "vef- 

 astigte" cells of Hanau (3), densely packed with the black- 

 brown granules. These cells correspond to the "trophoplasts" 

 of Heinke (13) observed in man. There is a central body 

 which sends out branches in all directions. In deeply colored 

 specimens these ramifying strands interlace and form a com- 

 pact network, which in many cases is so thick as to give the 

 impression of a homogeneous mass ; in others only isolated cells 

 are present. Here and there occur round or oval pigmented 

 bodies, which Hanau concluded were the starshaped cells with 

 their pseudopod-like appendages contracted. Pigment cells com- 

 monly lie around blood vessels clearly indicating their course. 

 They frequently form a fairly compact tube, but more often are 

 limited to fragments which only partly enclose the vessels. Ac- 

 cording to Hanau, pigment cells often appear as nerve endings. 

 Pigment cells are to be found in several well-defined localities ; 

 in the upper portion of the cutis among the closely interwoven 

 strands of connective tissue, in the region bordering the blood- 

 vessels, in proximity to nerves (3), and surrounding fat masses. 

 Isolated cells are frequently scattered at random through the 

 lower sections of the corium. The lower bodies of pigment play 

 little part in the color of the external shank, as they lie far be- 

 neath the opaque connective tissue. Melanin pigment granules 

 are always in the corium contained in pigment cells. When 

 found in the Malphigian layer, pigment cells were of an oval 

 form, no outrunners being observed, however it is probable that 

 other specimens would show them, as their presence is men- 

 tioned in this region in the dove in Hanau's monograph. In 



