130 CLASS AVES. 



the glottis was less plump, the abdomen extremely wide, and 

 the testes almost obliterated : the beak was of a leaden colour, 

 and the general tissue of the body relaxed and incompact. 



We find, upon the whole, that after the epoch of reproduc- 

 tion, the feathered race are less lively, less robust, and less 

 gay than before. They seldom sing, and their movements are 

 not characterised by the same rapidity and energy which they 

 displayed at the season alluded to ; — and, indeed, the same is 

 true of all other animals. 



We shall now make a few observations on the nidification 

 and incubation of birds. A remark, which we have had 

 occasion to make before, may with great propriety be repeated 

 here ; namely, that in almost all cases, the productions of 

 instinct are more perfect than those which emanate from 

 human ingenuity. The nidification of birds is one of the most 

 striking proofs that can be adduced of this, and is altogether a 

 subject of the most curious speculation. That it is a process 

 depending wholly upon iiniate impulse in the animal, and not 

 acquired by reason and experience, and transmitted from 

 generation to generation, is evident from the fact that birds, 

 placed under any circumstances, will build their nests as nearly 

 alike as their situation, and the materials afforded them, will 

 admit. Taken when quite young, or even hatched artificially, 

 they will build their nests when they breed in a state of captivity 

 as much as possible upon the model followed by their respective 

 species. This clearly proves that the art is intuitive, not 

 acquired ; for in such instances instruction is wholly out of the 

 question. 



Among the many pleasures attendant on the return of 

 spring, there are few more delightful to a contemplative mind 

 than to observe the proceedings of the monogamous races of 

 birds which people our groves and fields. They seem replete 

 with happiness, and intent on the performance of what we 

 consider in man some of the highest duties which he owes to 

 society. In the formation of an intimate union of affection and 



