Animals-. 217 



the Swan and Goose, have long necks and 

 short legs. 



Birds are destitute of urinary bladders 

 yet they have large kidneys and ureters, 

 by which the secretion of urine is perfor- 

 med, and then carried away with the oth- 

 er excrements, in one common canal ; by 

 which means they are less obnoxious to 

 diseases than quadrupeds, who drink much 

 and have a separate passage for the ejec- 

 tion of the fluid excrement. 



The greater number of Birds pair at the 

 approach of spring ; and the compact en- 

 tered into is inviolably observed, for that 

 season at least; but some species enter 

 into this connection for years, and even 

 for life. 



All Birds are oviparous, and the Hens 

 of some species will lay eggs though they 

 be not accompanied by the Male ; as the 

 common domestic Hen ; but eggs of this 

 kind are always sterile, never producing a 

 live ani mal. Every bird builds its nest in 

 such a manner, and with such materials, 

 as best to answer its own purpose and sit- 

 uation ; thus the Wren, which lays a great 

 number of eggs, requires a very warm 

 yies t ' 9 as her body is not sufficiently large ta 



