XIII 



PHYLUM CHORD AT A 



3S3 



contact (A, B). In this way the parts of the feather arc so bound 

 toe-ether that tlie entire structure offers crreat resistance to the air. 

 Among^ the contoitr featherfi which form the main coverinij of the 

 Bird and have the structure just described, are found jUoplumes 

 (Fig. 102.S, B), delicate, hair-like feathers having a long axis and a 



^^ 



<: 1 u i:^. X /a ^ t; 



few barbs, devoid of locking apparatus, at the distal end. Nestling 

 Pigeons are covered with a temporary investment of clown-feathers 

 (C), in which also there is no interlocking of the barbs : when these 

 first appear each is covered by a horny sheath like a glove-finger. 



Feathers, like scales, arise in the embryo from papilhe of the 

 skin (Fig. 1025, A, Pup.), formed of derm with an epidermal covering. 



