Fig. 5.

(A) Stage 36 (8–9 days) quail embryo, including limb detail. Quail embryos were killed, rinsed and fixed in 5% neutral buffered formalin before photography. (B) Schematic representation of the average pigmentation pattern observed at stage 36 on the wing and the dorsal surface of the embryo. Black and brown pigment is apparent in feather buds. Black pigmentation is present either side of the spine (tapering off in the region of the pelvis), overlying the scapula and ulna, and on the lateral aspects of the thigh and at the edges of the tail. There is a single line of black feathers in the region overlying the coracoids. Golden-brown pigmentation is also present but less extensive, with the most notable pigmentation being in the region of the tail. The beak length (mean length from the anterior angle of the nostril to the tip of the upper bill) is 1.2 mm and the third toe length (mean length from the middle of the metatarsal joint to the end of the most extreme digital pad on the third toe) is 3.2 mm.