176 ON GENERATION. 



dimensions; this pair was very much larger than any of the 

 others, and already prepared to descend into the second or lower 

 uterus. In these creatures, therefore, the number of young is 

 great, not because of the multitude produced at a time, but of 

 the frequency with which births take place, viz., every month. 

 In the same way, among cartilaginous fishes, such as the skates, 

 dog-fishes, &c., two eggs only come to maturity together, one of 

 which descends from the right the other from the left corner of 

 the uterus into the inferior portion, where they are cherished, 

 and where they finally produce living foetuses, precisely as hap- 

 pens among viviparous animals; in the ovary, nevertheless, 

 there is almost infinite store of ova of various sizes in the ray 

 I have counted upwards of a hundred. 



The ova of the other oviparous tribes are either perfected 

 externally, as in the case of fishes, or they are concocted or 

 matured, as in the instance of testacea, Crustacea, and spiders. 

 Testaceous animals lay their eggs amidst froth; the crusta- 

 ceous tribes, such as the shrimp, crab, and lobster, bear them 

 about with them, attached to certain appendages; and the 

 spiders carry them about and cherish them, laid up in a kind of 

 purse or basket, made of their web. The beetle rolls its eggs 

 in dung, using its hind legs in the operation, and buries them. 

 Now, in all these creatures the quantity of eggs is almost incre- 

 dibly great : in fishes they form two oblong bladders or folli- 

 cles, as may be seen in the carp, herring, and smelt, in all of 

 which, as there is no uterus, but merely an ovary present, so is 

 this sometimes crowded with ova to such a degree, that it comes 

 to surpass the body in bulk. 



Of such ovaries of the mullet and carp, salted and pressed, 

 and dried in the smoke, was prepared that article of food in 

 such request among the Greeks and old Italians, (called botorcha 

 by the latter, am rapt^a, i. e. salted eggs, by the former,) and 

 very similar, we may presume, to the masses which we find in the 

 iusides of our smoked herrings, and to the compact granular 

 red-coloured roe of our lobsters. The article prepared from 

 the salted roe of the sturgeon, which is called caviare, and re- 

 sembles black soap, is still the delight of epicures. 



In those fishes that are highly prolific such a quantity of eggs 

 is engendered, that the whole abdomen can scarcely contain 

 them, even when they are first produced, still less when they 



