INSTINCTS AND EMOTIONS IN FISH. 37 



rock among some interlacing branches of MyHophyllum spieatum — 

 all the time, however, frequently interrupting his labours to pay 

 his addresses to the females. This was done in most vigorous 

 fashion, he swimming, by a series of little jerks, near and about the 

 female, even pushing against her with open mouth, but usually 

 not biting. After a little coquetting she responds and follows 

 him, swimming just above him as he leads the way to the nest. 

 When there, the male commences to flirt — he seems unaware of its 

 situation, will not swim to the right spot, and the female, after a 

 few ineffectual attempts to find the proper passage into it, turns 

 tail to swim away, but is then viciously pursued by the male. 

 When he first courts the female, if she, not being ready, does not 

 soon respond, he seems quickly to lose his temper, and, attacking 

 her with great apparent fury, drives her to seek shelter in some 

 crevice or dark corner. The coquetting of the male near the nest, 

 which seems due to the fact that he really has not quite finished 

 it, at length terminates by his pushing his head well into the 

 entrance of the nest, while the female closely follows him, placing 

 herself above him, and apparently much excited. As he with- 

 draws she passes into the nest, and pushes quite through it, after 

 a very brief delay, during which she deposits her ova. The male 

 now fertilizes the eggs and drives the female away to a safe distance ; 

 then, after patting down the nest, he proceeds in search of another 

 female. The nest is built and the ova deposited in about twenty- 

 four hours. The male continued to watch it day and night, and 

 during the light hours he also continually added to the nest. 



The marine " 15-spined Stickleback," Gasterosteus spinachia, 

 affords another instance of nest-constructing fishes. The places 

 selected for their nests are usually harbours or some sheltered 

 spots to where pure sea-water reaches. The fish either find 

 growing or even collect some of the softer kinds of green or red 

 seaweed, and join them with so much of the coralline tufts (Janice) 

 growing on the rock as will serve the purpose of affording firm- 

 ness to the structure, and constitute a pear-shaped mass five or 

 six inches long, and about as stout as a man's fist. A thread, 

 which is elastic and resembles silk, is employed for the purpose 

 of binding the materials together ; under a magnifier it appears to 

 consist of several strands connected by a gluey substance, which 

 hardens by exposure to the water. In one instance the situation 

 selected was the loose end of a rope, from which the separated 

 strands hung at about a yard below the surface in five or six 



