Frogs and Toads 



moderately elaborate nests in hollows of marine pools, 

 using shells, corals, seaweeds, etc., in their construction. 



There are one or two examples of fishes which shelter 

 their eggs in their mouths after the manner of some toads. 

 Another fish, after his spouse has laid her eggs, blows from 

 his mouth a frothy substance, which causes the egg mass 

 to float upon the surface of the water ; this floating nest 

 he guards assiduously till the eggs hatch. 



None of these builders can compare with the pugnacious 

 sticklebacks, which, although they excel in nest-building, 

 are outdone in fighting powers by a little Siamese fish 

 bred by the natives and kept in captivity with the special 

 object of showing its fighting powers. So engrossed did 

 the Siamese become in the sport of fish fighting that, 

 about seventy years ago, it was necessary to obtain a 

 licence to exhibit such fishes, or rather their combats. The 

 fighting fish of Siam were the source of very considerable 

 revenue to the government. 



There are many species of sticklebacks and they are all 

 named according to the number of spines they carry on 

 their backs. The fifteen-spined stickleback is a common 

 marine fish and his three-spined brother is common in 

 ponds. A remarkable fact about the three-spined species 

 is that it may be transferred suddenly from fresh to salt 

 water without suffering the slightest inconvenience. 



Certain fishes, the salmon and eel to wit, can also live 

 in fresh or salt water, but the change from one to the 

 other must be gradual or the fish will suffer. The stickle- 

 back has only one tool for the construction of his elaborate 

 nest, and that tool is his mouth. His first care is to fix 

 on a suitable spot for his nest, and having done so, the 

 water in the immediate neighbourhood becomes his own 

 property ; no aliens may come within its bounds or they 

 will be compelled to run the gauntlet of the plucky little 

 fish's spines. And they form an armament by no means 

 to be despised. At rest they lie almost flat on his back ; 

 when he is alarmed the spines are erected like bristles on 



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