22
JACK COHEN
FIG. 11. Barb-ridge development under carefully controlled conditions of culture
(see Fig. 10). A-G, X 66; H, X 19. All cultures are of Brown Leghorn capon
breast pinfeather collar, except F, which is from wing primary pinfeather (virtually
equivalent periodicities were obtained from the two sources of tissue). For method,
see Table I, method 1.
A. 42.5°C. Twenty barb ridges per millimeter. Beautiful barb ridges, with
melanocytes almost in single file along them. (48 hr)
B. 33.0°C. This was scored from the live culture as "islands, no ridges"; however, in the picture it may be seen that the melanocytes in the center are aligned,
JACK COHEN
FIG. 11. Barb-ridge development under carefully controlled conditions of culture
(see Fig. 10). A-G, X 66; H, X 19. All cultures are of Brown Leghorn capon
breast pinfeather collar, except F, which is from wing primary pinfeather (virtually
equivalent periodicities were obtained from the two sources of tissue). For method,
see Table I, method 1.
A. 42.5°C. Twenty barb ridges per millimeter. Beautiful barb ridges, with
melanocytes almost in single file along them. (48 hr)
B. 33.0°C. This was scored from the live culture as "islands, no ridges"; however, in the picture it may be seen that the melanocytes in the center are aligned,