412 REMOVAL OF CHICK BLASTODERMS 



EXPLANATION OF CHICK PHOTOGRAPHS* 



Fig. 18- Visceral arches prominent, 65-69 hrs. , & 30-36 



somites. 



Fig. 19- Allantois developing, 68-72 hrs. , 37-40 S. 



Fig. 20 - Eye pigment present, 70-72 hrs. , 40-43 S. 



Fig. 21 - Limbs enlarge, 3. 5 days 43-44 somites. 



Fig. 22 - Somites to tip of tail, 3.5 days +. 



Fig. 25 - 4. 5 days 



Fig. 26 - 4.5 to 5.0 days 



Fig. 32 - 7.5 days 



Fig. 33 - 7. 5 to 8 days 



Fig. 34 - 8.0 days 



Fig. 35 - 8 to 9 days 



Fig. 42 - 16 days 



Fig. 43 - 17 days 



Fig. 44 - 18 days 



♦Some of these photographs were published by Dr. Nelson Spratt in Jour. Exp. Zool. 103:265 and 274j others by Hamburger and 

 Hamilton Jour. Morph. 88:49. All have since been published in Lillie's Development of the Chick, revised by H. L. Hamilton, 

 Copyright Holt, Rinehatt and Winston, Inc. 1952, and used here with permission. 



