rroceediiKjs. Ixxiii 



The carapace of tlie liawk's-bill turtle is covered with a scries 

 of liorny plates, which constitute the tortoisesliell of commerce. 



All birds are provided with a modified epidermic covering 

 constituting feathers. 



A typical feather- consists of three parts : the quill or barrel, 

 by which it is inserted in the skin ; the shaft or scape, which 

 bears on each side a series of flattened plates, the vane or web. 



These plates or barbs are placed obliquely on the shaft by tlieir 

 bases. Their edges bear numerous smaller processes called bar- 

 bules, and these in their turn, in the most perfect feathers, are 

 fringed with still smaller barbicels or booklets, by which tlie 

 biirbs are held together, so as to present a resisting surface to the 

 air. 



The accessory plume or plumule, formed at the junction of the 

 shaft, was then described. This attains its greatest develop- 

 ment in the feathers of the emu and cassowarj', being in these 

 birds almost as large as the main feather. It is never developed 

 on the large wing and tail feathers, and is entirely wanting in all 

 feathers in some groups. 



The forms of feathers vary with their position on the body of 

 the bird and the purposes to which they are adapted. In the 

 down-feathers the stem is not much developed, and the soft barbs 

 have long slender barbules with knotty dilatations in place of 

 barbicels. In the thread-feathers the barbs are rudimentary or 

 altogether wanting. The ends of the shafts in some abnormal 

 cases are developed into horny expansions, as in the secondary 

 feathers of the waxwing, &c. 



The author remarked that the great beauty of the plumage of 

 birds led in many instances to their wholesale and wanton 

 destruction, and expressed a hope that the provisions of the 

 Wild Birds' Protection Act would be rigidly enforced, and, if 

 need be, extended. He regretted also that so many birds were 

 annually sacrificed at the dictates of fashion, for the purpose of 

 adorning hats and bonnets, a most unnecessary proceeding in the 

 presence of more attractive charms. He considered that birds 

 mounted in cases and surroundings which closely imitate their 

 natural haunts gave delight and instruction to many who would 

 otherwise have no opportunity of seeing them. 



In the Mammalia, the highest division of Vertebrates, some 

 part or other of the integument is always provided with hairs at 

 some period of life. 



Hairs are modified epidermic formations. Each is embedded 

 in a hair-follicle, formed by an inversion of the skin. The 

 portion at the bottom of the follicle is dilated into the bulb, 

 which encloses a softer vascular bod^y, the papilla or pulp ; and it 

 is by the continual augmentation of this pulp and its gradual 

 conversion into horny matter that the growth of the hair is due. 



