VOL. LVII.] PHILOSOPHICAL TRANSACTIONS. 443 



column contains the names of the fish he examined ; the 2d their weight ; the 

 3d the weight of their spawn ; the 4th their fecundity ; and, as he supposed 

 some persons might be desirous to know how large a portion of spawn he weighed 

 in each case, he set down the number of grains in each such portion, in a 5th ; 

 the number of eggs found in a grain, by this method is seen in a 6th, by which 

 we may give some guess at the different sizes the eggs of each species are of, 

 when they are excluded ; and he made the time of examining each fish respect- 

 ively a 7 th ; which possibly may be of some use to those who may have an in- 

 clination to repeat any of these observations, as from thence may be learnt some- 

 thing concerning the most advantageous time of examining these creatures, 

 which certainly ought to be as nearly as we can, when the eggs are come to their 

 full size, and before any of them are deposited. However, after all, if his 

 notion is just, that some species deposit a part of their eggs come to their full 

 growth, before others laid the same year are large enough to be told with dis- 

 tinctness, the accounts of the fecundity of such fish must be extremely defective; 

 this he apprehends, among those he examined, is the case of mackarel, carp, tench, 

 and others ; in the eggs of herring, &c. there does not appear such a difference 

 From this table it appears, that the size of the eggs is nearly the same in 

 great and small fishes of the same species, at the same time of the year ; that the 

 quantity of spawn is, usually, nearly proportionate to the size of the animal ; 

 whence we may give a tolerable guess at the greatest fecundity of each species, 

 if we know to what weight they have been found to grow, while in a breeding 

 state ; we may likewise settle their produce at a medium, on learning what is the 

 mean size of each species when in the forementioned state ; but we see however 

 that this is not universal, nor consequently perfectly exact, some fish being much 

 more prolific than others of the same size and species. 



To conclude, the great fecundity of fish is not the only thing that affects 

 the imagination, when we are examining matters of this sort : the extreme dis- 

 proportion between their size when they first appear in the water after hatching, 

 and that of their full-grown state, as well as the little proportion that is to be 

 observed between the bulks of fish of different species and that of their eggs, are 

 things that are very amazing to persons of a curious turn. The egg of a smelt, 

 which at its full growth weighs but 2 or 3 ounces, appeared, in those he exa- 

 mined, to be larger than those of a cod-fish, which weighed 1 8 or 20 pounds, 

 and might have grown to double that bulk ; and that of a stickle back, which is 

 the smallest of all known fish, was found to be above 6 times larger than the 

 largest he ever observed in a smelt. What becomes of such amazing numbers 

 of young fish, and why some are made so extremely prolific, the flounder and 

 crab in particular among the smaller sorts, would doubtless be highly entertain- 

 ing subjects, if duly illustrated. 



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