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however they may differ, an analogy can always be detected, even between 

 the most opposite forms, through a number of connecting links. 



On the present occasion we shall confine ourselves to a history of hair, 

 fur, and wool, and merely indicate en passant its connection with other 

 varieties. 



If we examine hair in the vegetable world, we shall find that the type 

 is simple. It consists of a minute pointed cell, continuous with, and 

 attached to, the epidermis. A single cell is rarely met with, two or more 

 usually making up the hair ; according to the relative size and shape of 

 these cells, we have acuminated, knobby, beaded, or other forms. 



If the number of cells becomes greatly multiplied, we find the shapes 

 assumed as singular as they are beautiful. We have tables and stars, 

 spears and shields, arrows and horns. In some there is a development 

 of a poisonous material, and in the stinging hairs of the nettle we have 

 a resemblance to the fearful fangs of the serpent. 



The greatest departure from the usual type is to be seen in the almost 

 bony spines of the skin of the dog rose, where the once soft cells have 

 become converted into a tissue harder than the wood itself. 



In the fera and allied genera, the original type has almost disappeared, 

 and is replaced by scales. 



After this short account of hairs in the vegetable kingdom, w^e shall 

 be prepared to find a similar diversity in the animal. 



The simplest form of hair in the auimal kingdom is a single elongated 

 cell, and is met with chiefly in the insect tribes. 



From this type we may trace many varieties. 



In the caterpillar of the tiger moth, we have the simple hair, singly 

 branched, a number of points projecting from its sides, whose cavities 

 are continuous with that of the parent stem. 



In the spider, these points are increased both in number and length, 

 so that each hair bears a resemblance to a feather. In some, tertiaiy 

 points exist which increase the resemblance. The same may be said of 

 the swimming hairs of most of the crustacae, as the shrimp, lobster, &c. 



In one specimen in my possession, marked " hairs of a caterpillar," the 

 branches from the central stem are sparse, except at the summit, where 

 they ajre given off in large masses similar to the long feather of the 

 peacock. 



Having pursued, by gradual steps, a simple hair to a highly compUcated 

 one, and shown its diverging into feather, we again turn back and titice 

 it to another form. 



If we examine the wing of certain butterflies, (Ithamaea and Heliconia, 

 for example,) we shall find, near its junction with the body, a few simple 



