%;6 THE PHILOSOPHY 



of living, and the oeconomy of the animal, is the invariable 

 refult. 



Like the amphibious animals, a number of fowls live chief- 

 ly in the water, and feed upon filhes and aquatic infedts. 

 To enable them to fwim and to dive in queft of food, their 

 toes are conne£led together by broad membranes or v/ebs. 

 By ftretching their toes, and fLriking the water backward 

 with thefe webs, their bodies are movecl forward, and they 

 employ their tail as a rudder to direct their courfe. With- 

 out thefe additional inftruments, fowls could not fwim ; and, 

 accordingly, fuch birds as are not provided v/ith vv^ebs never 

 take to the water. But thofe furnifhed with webs have fuch 

 a ftrong propenfity to water, that, when reftrained from 

 their favourite element, they difcover the greateil uneafinefs, 

 and, when their liberty is reftored, they fly in a direct ccurle 

 either to the fea, a river, or a lake. 



There is another tribe of aquatic birds, fome of which 

 feed upon fifhes and infecls, and others live principally by 

 fucking certain juices from mud. Both thefe kinds frequent 

 marfhy places, or the margins of lakes and rivers. They 

 do not fwim, but v;ade, in quefl of food. This Angularity 

 in their manners required a correfpondent variation in theii" 

 form and ftruclure. To enable them to wade in waters and 

 in mires. Nature has provided them with long legs, naked of 

 feathers for a conliderable {pace above the knees. Their 

 toes are not, like thofe of the fwimmers, conneded by con- 

 tinued membranous webs. Moft of them have likewife 

 very long necks and bills, to enable them to fearch for and 

 apprehend their food. To thefe tribes belong the crane, the 

 heronS;, the bittern or miredrum, the ftork, the fpoon-biil, 

 the woodcock, the fnipe, and many other fpecies. 



Having given a general idea of the ftructure and ©econo- 

 my of birds, we fliail next make a few remarks on the form 

 and manners of fifhes. 



