FRESH-WATER FISH AND MOLLUSCA. 63 



all pigmy fish, that may be chosen with discrimination for 

 the Aquarium. 



The Stickleback, which is also termed the Prickleback, 

 on account of the small spines with which nature has 

 armed it for defence, is one of the tiniest of all fish, be- 

 sides being one of the most interesting!- Though a dap- 

 per little fellow, very active and very courageous, he 

 would soon fall a prey to all his companions, on account 

 of his dwarfish, size, were it not for the stiff, sharp, prickly 

 arrangement, like a row of fixed bayonets, which embel- 

 lishes the lower surface of his body. He can erect this 

 at pleasure ; and in that condition it is impossible for 

 his natural antagonists to make a mouthful of him with- 

 out seriously lacerating themselves, particularly as he is 

 an irritable little creature, and remarkably pugnacious. 

 With this weapon at command, he plunges into an im- 

 promptu quarrel, occasionally, with fish of considerable 

 magnitude, and has been known to rip up their stomachs 

 in his ferocity, leaving them dead upon the field of 

 combat. Indeed, the stickleback is so mettlesome, and in 

 his habits so belligerent, that when several are placed in 

 a tank together, the males often make it a point to com- 

 mence with a severe battle to determine which shall pos- 

 sess the favorite females of the company, and which shall 

 be entitled to the choicest localities of their new domain. 

 In this engagagement death sometimes ensues ; for the 

 victor seldom gives the conquered much peace, unless 

 quite exhausted himself in the struggle. The females in 



