OF THK MILK. 39- r > 



the mammalia in general : some animals being thus oviparous, 

 others ovoviviparous, and others viviparous. 



The mode of nourishment after birth is various. Some are 

 able, without any peculiar arrangement, immediately to support 

 themselves ; for the wisdom of the Creator ordains the delivery 

 of each species of animals at that season of the year when every 

 thing is in the most favourable state for administering to the 

 necessities of the offspring. Some, many insects for example, are 

 born in the midst of food, the parent having instinctively deposited 

 the egg in nutrient matter either found in mass or carefully col- 

 lected by her. Others have food collected daily by the parents. 

 Some, as all the dove kind, are fed by a substance secreted from 

 the crops of both parents ;* others by a fluid secreted by peculiar 

 glands belonging to the female only.f The instinct which leads 

 the parent carefully to tend the offspring, ceases at the period when 

 the system of the offspring is sufficiently advanced to supply its 

 own exigencies, and the parent does not breed again till this is 

 the case. 



* Hunter, On a secretion in the crops of breeding- pigeons for the nourishment 

 uf their young, in his Observations on certain parts, ffc. p. 235. 



f- Mr. Hunter satisfied himself experimentally of the truth of the common 

 assertion, that the she-ass gives milk no longer than the impression of the foal 

 is upon her mind. The skin of her foal thrown over the back of another, 

 and frequently brought near her, is sufficient. Journal of the Royal Institu- 

 tion. No. 2. 



