BONY FISHES AND GANOIDS. 



three to as many as fifteen. All are comparatively small fishes, and whereas 

 the majority are inhabitants of fresh waters, a few are marine. What they 

 lack in size, they make up for in fierceness, sticklo-backs being perfect 

 demons for fighting among themselves, while they are terribly destructive to 

 the spawn and fry of larger and better fishes. They have, however, the redeem- 

 ing quality of taking most excellent care of their own eggs and young, for the 

 reception of which the male builds a nest, which he guards with vigilance, 

 and, if necessary, with his life. Not only is this nest-building habit found in 

 the fresh- water species, but it is likewise common to the sea stickle-back of 

 the British coasts, which selects for its site of operations shallow brackish 

 water, where sea-weeds are abundant. Among many anecdotes relating to 

 the voracity and pugnacity of stickle-backs, we select one from the pen of 

 Mr. J. Stark. On one occasion this gentleman placed in the water inhabited 

 by a stickle-back a number of leeches. Thereupon the fish " darted round 

 the tumbler with lively motions till it found a leech detached and in a proper 

 situation for being seized. When the leech was very small, say about half 

 an inch in length, it was often swallowed at once, before it reached the 

 bottom of the vessel ; but when a larger one, about an inch or an inch and a 

 half in length in its expanded state, was put in, and had fastened itself by its 

 mouth to the glass, the eiTorts of the stickle-back to seize and tear it from its 

 hold were incessant, and never failed to succeed. It darted at the loose ex- 

 tremity, or, when both ends were fastened, at the curve in its middle, seized 

 it in its mouth, rose to near the surface, and after a hearty shake (such as a 

 dog would give a rat), let it drop. The leech, which evidently wished to avoid 

 its enemy upon its release, again fastened itself by its mouth to the glass ; 

 but again and again the attack was repeated, till the poor leech became ex- 

 hausted, and ceased to attempt to hold itself by its disc. The stickle-back 

 then seized it by the head in a proper position for swallowing, and after a few 

 gulps the leech disappeared. The flattened leech being of an oval form, and 

 having a hard skin, was not attacked, unless when very young and small ; 

 and leeches of the other species, when pretty well grown, or larger than him- 

 self when expanded, were killed in the manner above mentioned, but not 

 swallowed. In one of his attempts to seize a leech, the stickle-back having 

 got it by the tail, the animal curled back, and fixed his disc upon his 

 snout. The efforts of the stickle-back to rid himself of this encumbrance 

 were amusing. He let go his hold of the leech, which then hung over his 

 mouth, and darting at the sides and bottom of the glass with all his strength, 

 endeavoured to rub off this tantalising morsel. This lasted for nearly a 

 minute, when at last he got rid of the leech by rubbing his back upon the 

 bottom of the vessel. The leech, perfectly aware of the company he was in, 

 no sooner loosed his hold than he attempted to wriggle away from his de- 

 vourer ; but before he had reached mid-way up the tumbler, the stickle-back 

 had turned, and finished the contest by swallowing him up." 



The second family of the section, which comprises the flute-mouths 

 (^itiosioma, Auliscojjs, and Fistularia), is readily characterised by the pro- 

 duction of the muzzle into a long flute-like tube, at the 

 extremity of which is situated the small mouth ; and, like- Family 



wise, by the pelvic fins, which may be either thoracic or Avlostomalidce. 

 abdominal, comprising six (rarely five) soft rays and no spine. 

 When they are abdominal they have no connection with the pelvis, which is 

 always attached to the pectoral girdle. Whereas in some forms the body^ — 

 which is always much elongated — is completely naked, in others minute scales 

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