176 



FIRST BOOK OF ZOOLOGY. 



o, 



A £ O 



Fig. 154. — Embeyo Bikds in Vaeiotjs Stages of Development.—^, Chipping Sparrow; 

 B, Petrel; G, Tern Been from above. 



If, now, the bones of the wing of an embryo bird be ex- 

 amined, the bones of the extremity of the wing, instead of 



Jmmerus 



carpus 



•metacarpus 



phalanges 



Fig. 155. — Eight Wing of an Embeyo Bird geeatlt enlarged. — Only a portion of 

 the humerus is seen. 



