The pattern of muscle development in the chick leg.

Abstract

The splitting pattern and the spatial arrangement of the musculature were studied in the chick tibiotarsal segment. All 15 muscles evolve from the two opposed premuscular masses which become dorsal and ventral to the chondrogenic core before day 5 of incubation. Binary and tertiary divisions and subdivisions of these muscle masses between day 5 and day 7.5 of incubation produce the muscular pattern characteristic of the hind limb zeugopod.