SELEf'TINf! EGOS FOR SITTING 



40.3 



Fig. 144. — Abdominal yolk, the baby chick's food. Note the abdominal 

 yolk nearly filling the abdominal cavity of top chick which is just hatched. 

 In the middle picture the arrows point to the yolk sac, the left from chick 

 43 hours old, the right from chick 77 hours old. The lower chick lOS hours 

 old aud_jiext ahQ3/.« ft6 h*uPB-0tdo — 



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