ANIMALS. 287 



pains Nature takes in the formation of her lower and humbler 

 productions. As the removal of these from inanimate into ani 

 mal existence is but small, there are but few preparations made 

 for their journey. No organs of generation seem provided, no 

 womb to receive, no shell to protect them in their state of tran- 

 sition. The little reptile is quickly fitted for all the offices of 

 its humbler sphere, and in a very short rime, arrives at the height 

 of its contemptible perfection. 



The next generation is of those animals that we see produced 

 from the egg. In this manner all birds, most fishes, and many 

 cf the insect tribes, are brought forth. An egg may be con- 

 sidered as a womb detached from the body of the parent animal, 

 in ^'■hich the embryo is but just beginning to be formed. It 

 may be regarded as a kind of incomplete delivery, in which the 

 animal is disburthened of its young before its perfect forma- 

 tion. Fishes and insects, indeed, most usually commit the care 

 of their eggs to hazard : but birds, which ai-e more perfectly 

 formed, are found to hatch them into maturity by the warmth 

 of their bodies. However, any other heat, of the same tempera- 

 ture, would answer the end as well ; for either the warmth of 

 the sun, or of a stove, is equally efficacious in bringing the ani- 

 mal in the egg to perfection. In this respect, therefore, we may 

 consider generation from the egg as inferior to that in which the 

 animal is brought forth alive. Nature has taken care of the 

 viviparous animal in every stage of its existence. That force 

 which separates it from the parent separates it from life ; and 

 the embryo is shielded with unceasing protection till it arrives 

 at exclusion. But it is different with the little animal in the 

 egg ; often totally neglected by the parent, and always separ- 

 able from it, every accident may retard its growth, or even des- 

 troy its existence. Besides, art or accident, also, may bring 

 this animal to a state of perfection ; so that it never can be con- 

 sidered as a complete work of natiu-e, in which so much is left 

 for accident to finish or destroy. 



But however inferior this kind of generation may be, the ob- 

 servation of it will afl^ord great insight into that of nobler ani- 

 mals, as we can here watch the progress of the growing embryo 

 in every period of its existence, and catch it in those very mo- 

 ments when it first seems stealing into motion. Malpighi and 

 Hailer have been particularly industrious on this subject j and 



