126 



A HISTORY OF 



their prey, and the food of any one of them 

 serving for the nourishment, and circulating 

 through the bodies, of all the rest. This so- 

 ciety, however, is every hour dissolving; 

 those newly produced are seen at intervals 

 to leave the body of the large polypus, and 

 become, shortly after, the head of a begin- 

 ning colony themselves. 



In this manner the polypus multiplies na- 

 turally; but one may take a much readier 

 and shorter way to increase them, and this 

 only by cutting them in pieces. Though cut 

 into thousands of parts, each part still retains 

 its vivacious qualities, and each shortly be- 

 comes a distinct and complete polypus; whe- 

 ther cut lengthways or crossways, it is all 

 the same : this extraordinary creature seems 

 a gainer by our endeavours, and multiplies 

 by apparent destruction. The experiment 

 haS been tried, times without number, and 

 still attended with the same success. Here, 

 therefore, naturalists, who have been blamed 

 for the cruelty of their experiments upon 

 living animals, maynow boast of their increas- 

 ing animal life, instead of destroying it. The 

 production of the polypus is a kind of philo- 

 sophical generation. The famous Sir Tho- 

 mas Brown hoped one day to be able to 

 produce children by the same method as 

 trees are produced : the polypus is multi- 

 plied in this manner; and every philosopher 

 may thus, if he please, boast of a very nume- 

 rous, though, I should suppose, a very useless 

 progeny. 



This method of generation, from cuttings, 

 may be considered as the most simple kind, 

 and is a strong instance of the little pains 

 nature takes in the formation of her lower 

 and humbler productions. As the removal 

 of these from inanimate into animal existence 

 is but small, there are but few preparations 

 made for their journey. No organs of gene- 

 ration 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 humble sphere, and, in a 

 very short time, 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 of the 

 insect tribes, are brought forth. An egg may 



be considered as a womb, detached from the 

 body of the parent animal, in which the em- 

 bryo is but just beginning to be formed. It maj 

 be regarded as a kind of incomplete delivery, 

 in which the animal is disburdened of its 

 young before its perfect formation. Fishe* 

 and insects, indeed, most usually commit the 

 care of their eggs to hazard; but birds, 

 which are more perfectly formed, are found 

 to hatch them into maturity by the warmth 

 of their bodies. However, any other heat, 

 of the same temperature, would answer the 

 end as well; for either the warmth of the 

 sun, or of a stove, is equally efficacious in 

 bringing the animal 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 ani- 

 mal in every stage of its existence. That 

 force which separates it from the parent, se- 

 parates it from life ; and the embryo is shield- 

 ed with unceasing protection till it arrives 

 at exclusion. But it is different with the lit- 

 tle animal in the egg ; often totally neglected 

 by the parent, and always separable from it, 

 every accident may retard ita growth, or even 

 destroy its existence. Besides, art or acci- 

 dent, also, may bring this animal to a state 

 of perfection ; so that it can never be consi- 

 dered as a complete work of nature, in which 

 so much is left for accident to finish or de- 

 stroy. 



But, however inferior this kind of genera- 

 tion may be, the observation of it will afford 

 great insight into that of nobler animals, as 

 we can here watch the progress of the grow- 

 ing embryo in every period of its existence, 

 and catch it in those very moments when it 

 first seems stealing into motion. Malpighi 

 and Haller have been particularly indus- 

 trious on this subject; and, with a patience 

 almost equalling that of the sitting hen, have 

 attended incubation in all its stages. From 

 them, therefore, we have an amazing history 

 of the chicken in the egg, and of its advances 

 into complete formation. 



It would be methodically tedious to de- 

 scribe those parts of the egg which are well 

 known, and obvious ; such as its shell, its 

 white, and its yolk; but the disposition of , 

 these is not so apparent. Immediately under 



