NATURAL HISTORY. 
FISHES. 
The Class of Fishes possesses a greater number 
of known species than any other of the primary 
divisions of Vertebrate animals ; perhaps, in- 
deed, when we consider the ratio which water 
bears to land on the surface of our globe^ and 
the peculiar difficulties which attend the study 
of these animals, it may not be extravagant to 
suppose that the species of Fishes exceed in 
number those of Mammalia, Birds, and Reptiles 
put together. The number of individuals, also, 
composing the different species, in general, much 
exceeds the average as found in the other Classes, 
arising as well from the extent and depth of 
the element which they inhabit, as from their 
astonishing fecundity. The eggs of a bird are 
reckoned numerous when they amount to a score, 
but the eggs of fishes are commonly counted by 
thousands, and in some cases even by millions ! 
In the ovary of a Cod, nine million eggs have 
been ascertained to exist, and Mr. Jesse asserts 
that the ovary of one female Salmon will pro- 
duce twenty million eggs.” When we add that 
fishes yield an immense quantity of agreeable 
B 
