86 BRITISH FRESH-WATER FISHES 
his sufferings, took him out of the tank and placed him 
elsewhere. 
It is a remarkable thing that, whereas the size of most 
predaceous fish seems to have no defined maximum limit, but 
depends directly upon the amount of food secured, that of 
the stickleback remains fixed. Thus, while the pike attains the 
weight of 25 lb., 30 lb., 40 Ib., and even more in well-authenti- 
cated instances, there are numerous lakes, where the food 
supply is limited, where it rarely reaches 10 Ib. But in the 
case of the stickleback, feed it never so generously, it will not 
much exceed the length of three inches. Mr. Keene mentions 
that he has seen sticklebacks fall victims to their own voracity, 
the spines having become entangled in the glutinous substance 
surrounding frog spawn on which the fish had attempted to 
make a hearty meal. 
The three-spined stickleback, in its various varieties of 
form, is very widely spread over the waters of Temperate 
and Arctic Europe; and closely allied forms, dis- 
tinguished dubiously as species, inhabit the waters 
of Greenland and North America. But none of the genus 
have been identified in the tropics, nor in the Southern Hemi- 
sphere. I do not know that this fish is turned to any economic 
use at the present time in Britain, but Pennant mentions the 
extraordinary numbers which used to appear in certain years 
in the river Welland at Spalding, where the peasantry used 
to scoop them out in millions, and apply them as manure to 
the land. They used also to boil them for the oil they con- 
tained, as is done in Sweden and France at this day. Some 
idea of their abundance may be had from an instance cited by 
the aforesaid writer, namely, of a man employed by a farmer 
to collect sticklebacks for manure, who was paid at the rate of 
one halfpenny per bushel, and earned in the season at the 
rate of four shillings a day. It has been observed that the 
stickleback is very scarce in the Thames. It is quite at home 
in brackish, and even in salt, water. 
Distribution. 
