Date of Award

Summer 1951

Degree Type

Thesis - Restricted

Degree Name

Master of Science (MS)



First Advisor

Saunders, John W.

Second Advisor

O'Brien, John P.


This paper attempts to localize, in general, the areas in the leg-bud of the 3-4 day embryonic chick which give rise to the future leg-parts. In addition, it hints at the presence of a zone of apical growth in the tip of the leg-bud by virtue of the progressive laying-down of future leg-parts in the apex of the bud and the subsequent elongation of these parts. In so doing it is essentially a continuation, in part, of the work of Saunders ('48) on the proximo-distal sequence of origin of the parts of the chick wing.