250 maine agricultural experiment station. i914. 



Description of Figures. 



All figures were drawn at an approximate magnification of 300 

 diameters. In reproduction they have been reduced by one- 

 fourth. Drawings were made from unstained free-hand vertical 

 sections through the shank skin of the domestic fowl. 



Though lipochrome pigment is frequently found in the corium 

 no effort was made to obtain sections which showed it, as its 

 presence has no bearing on the color of the skin and it is difficult 

 to represent it in small quantities in uncolored drawings. 



The following characters have the same significance in all of 

 the drawings : 



C. — Portion of the corneum. 



M.— Rete of Malphigi. 



F. — Flattened cells of the rete of Malphigi. 



T. — Transition cells of the rete of Malphigi. 



B. — Columnar cells of the rete of Malphigi. 



D. — A portion of the corium or demis. 



G. — Melanin pigment granules. 



P. — Melanin pigment cells. 



Y. — Lipochrome pigment diffused through cells. 



V. — Melanin pigment bordering blood vessels. 



Fig. yj. A vertical section of skin from the shank of a white 

 legged hen. Neither melanin nor lipochrome pig- 

 ment is present. 



Fig. 78. A vertical section of skin from the shank of a yellow 

 legged hen. Lipochrome pigment is diffused 

 through the epidermis. Melanin pigment is want- 

 ing. 



Fig. 79. A vertical section of skin from the shank of a blue 

 legged hen. Melanin pigment cells are thickly scat- 

 tered through the upper dermis. The epidermis is 

 free from either type of pigment, and there is no 

 lipochrome pigment in the corium. 



