﻿EXTERNAL ANATOMY. THE NECK. 27 



goatsuckers, &c, is in some measure attributable to the 

 same cause, although in a far less degree. 



(36.) The neck attaches the head to the body : some- 

 times this part is very long, not only in birds, but in 

 certain quadrupeds. The use, however, of this unusual 

 prolongation is various. In the Camelopardalis it enables 

 the animal to reach the branches of the tall mimosas, 

 whose leaves constitute its chief nourishment. In the 

 perching order of birds, Insessores, the only examples of 

 this sort are found among the woodpeckers*, whose pe- 

 culiar method of picking holes in trees, by the force of 

 repeated strokes of the bill, obliges them to throw the 

 head very backward without elevating the body : this 

 they are enabled to do by their long neck ; an additional 

 force, or impetus, is thus given to every blow, just as a 

 person who wishes to strike hard with a hammer, ele- 

 vates his hand in proportion to the blow he wishes to 

 produce. Nearly all other insessorial birds have short 

 necks, for no such exertion as we have just described is 

 requisite to procure their food; and their constant habit 

 of perching on the branches of trees, renders it unneces- 

 sary that they should be more elevated for the purpose of 

 discerning the approach of danger. Among birds, how- 

 ever, which have feeble wings and live habitually upon 

 the ground, like the rasorial order, the neck is much 

 more developed. This may be intended to effect two 

 purposes : first, to give a greater scope of vision, as a 

 security against danger ; and, secondly, to facilitate the 

 act of feeding. It is evident that birds attach the feel- 

 ing of security to elevation ; for nearly all those which 

 habitually live only upon the ground, roost in branches, 

 where they can see much farther, and discern the ap- 

 proach of an enemy. On the other hand, as the 

 gallinaceous order, like the turkey and the peacock, 

 have generally high legs, a long neck is essential to 

 avoid any difficulty in feeding and picking their food 

 from the ground, close to which the head must reach 



* This is doubtless one of the analogies between the herons and the 



