THE FAMILY-LIFE OF FISHES. jjj 



THE FAMILY-LIFE OF FISHES. 



Bt KARL HENNINGS. 



AMONG the nest-building fishes which inhabit German waters, 

 the most interesting is the tiny " stickleback," whose life-history 

 has been carefully studied. The home of this little animal is some- 

 times found in ditches, hanging among branches and twigs of plants ; 

 the nest is about the size of the average hand, and in structure and 

 material bears a marked resemblance to the round nest of the tit- 

 mouse. It is a peculiar and remarkable fact that among the stickle- 

 backs the hatching is done by the male and not by the female fish. 

 The building of the nest, a task to which the male also attends, is an 

 interesting event. For many days in succession the little animal, whose 

 energy and perseverance are truly worthy of admiration, collects its 

 material, which consists of loose stalks, plant-shreds, root-fibers, and 

 grass. These it assorts carefully, discarding all material that proves 

 too light. It often drags along pieces exceeding its body in length, 

 and sometimes with great exertion strips growing plants. All this 

 material is worked up into a tangled mass, and layers of sand are scat- 

 tered in between. The nest is rendered firm by a glue-like juice, which 

 the little mason excretes after the completion of each layer, gliding 

 slowly over the structure ; this causes the separate parts of the nest 

 to adhere closely together. The whole, when completed, has the ap- 

 pearance of a sand-hill, and is detected with much difliculty. While 

 at work the fish rai-ely partakes of any food ; it seems that during 

 this blissful period of its existence it finds no pleasure in such every- 

 day events ; but with intense animosity it drives back any jealous 

 rivals, larvae, salamanders, or water-bugs, which cross its path, some- 

 times with evil sometimes with harmless intentions. After the trouble- 

 some hatching-time is over, the anxious papa still continues to care for 

 his numerous offspring ; by day and by night he watches over them, 

 and drives away all creatures whose approach seems dangerous. This 

 unremitting watchfulness ceases only when his young are able to raise 

 their weapons of defense and have become somewhat acquainted with 

 their surroundings. Any inquisitive little one venturing too far away 

 is quickly sent home, and it actually happens that those who are very 

 disobedient are imprisoned in the ncsf. The home-life of these little 

 animals really presents an abundance of interesting and touching 

 traits. 



To study the family of fishes which inhabit the ocean and sea-gulfs 

 is naturally more diflftcult, and rarely proves as successful as observa- 

 tion extended to the inhabitants of our fresh-water lakes, rivers, and 

 streams ; but, by the co-operation of naturalists, fishermen, and sailors, 

 many events happening in the deep seas have been observed that afford 



