430 ANIMAL LIFE-HISTORIES 



that is apparently done is to make the ball of oddments suffi- 

 ciently large — a process which has entailed many wild dartings 

 about, and much poking and arranging with noses; and then 

 one of them, generally again the male, makes a dart at the 

 ball, or they do so in turns, and attempt to wriggle themselves 

 through the middle of it. The object is to make a kind of 

 tunnel right through, which is at last accomplished, and that 

 is the nest. But there is a good deal of fussy procedure after 

 that, or some mysterious arrangement is made inside, since, 

 for a few days longer, material is often shot in or shot out; 

 and sometimes, after it has been completed, it isn't thought 

 sufficiently snug, and material is added on the outside. And 

 they are clever little builders, for a house of theirs might be 

 constructed under your very nose and you would probably not 

 see it." This account may be supplemented by facts which 

 other naturalists have ascertained. The nest has at first only 

 one opening, and is made by the male, who is decidedly poly- 

 gamous. When the nursery is ready he conducts his consorts 

 to it one after the other, each laying from two to four eggs, 

 after which they swim away and take no farther interest in 

 domestic concerns. The second opening in the nest is made 

 by the first female after laying her eggs, for instead of backing 

 out she forces her way out through the further wall of the 

 cavity. The existence of two apertures is favourable to de- 

 velopment, for it promotes a constant flow of fresh water 

 through the nest. When all the eggs have been laid the male 

 stickleback, arrayed in brilliant war-paint, guards the nursery 

 jealously till the young hatch out, which takes place in about 

 ten days. Nor is his task a sinecure, for the time is spent in 

 continual combat with other sticklebacks, especially females, who 

 constantly try to reach the nest for the purpose of eating the 

 developing eggs. After hatching has taken place the father pro- 

 tects the fry till they are large enough to look after themselves. 



Sticklebacks have been treated at length, not only because 

 their ways are particularly interesting, but also because anybody 

 can easily stock a small freshwater aquarium for himself, and 

 become an eye-witness of the curious domestic drama above 

 described, which is enacted about mid-spring. Similar habits 

 characterize our smaller native species, the Ten-spined Stickle- 

 back, or "Tinker" {Gasterosteus pungitms), in which the male 



