THE STICKLEBACK 85 
pulls the home to pieces, and the family assembles on the 
ruins. In the larval form the young fry are provided with 
natatory membranes extending the whole length of the body. 
At the age of twelve days or so these are absorbed as the 
fins and spines begin to appear, and shortly afterwards a 
colony of perfect little fishes swims forth to take the chances 
of this unequal world. 
It is a strange history, which any one may verify for him- 
self. So entirely are the cares of the family concentrated in 
the male that, should he be captured or otherwise come to 
grief during his period of guardianship, the nest is torn to 
pieces by other sticklebacks and the contents devoured. It 
is supposed that in the manner described the male stickleback 
usually constructs three nests, and rears as many broods of 
from sixty to one hundred and twenty fry in the course of 
a single season. 
In spite of its diminutive form, and, proportionately, still 
more diminutive mouth, this stickleback destroys a prodigious 
number of the young of other fish. Gunther records that a 
single stickleback confined in an aquarium devoured, in five 
hours’ time, ‘‘seventy-four young dace, which were about a 
quarter of an inch long, and of the thickness of a horsehair. 
Two days after it swallowed sixty-two, and would probably 
have eaten as many every day could they have been procured. 
Nor have these restless little creatures any respect for larger 
fish. Mr. Houghton tells of a small pike which he kept in 
the same tank with some sticklebacks. The little wretches 
were perpetually nibbling at the pike’s tail fin, which is as 
though a pack of school-children should amuse themselves 
by twisting the tail of a tiger. Often the larger fish 
would dash among his tormentors, and, seizing one of them, 
try to swallow it. He never succeeded; the spines were 
too much even for jaws so well armed, and the malefactor 
was speedily ejected. Day by day the luckless pike’s tail 
fin diminished in size, till Mr. Houghton, commiserating 
