280 PUGNACITY OF THE MARINE STICKLEBACKS. 



armed at all points for warfare, protected at the sides by 

 shell-like plates, and with spears that play terrible havoc 

 among the Crustacea and small animals on which they feed. 

 They are objects of peculiar interest from the beauty of 

 their colors, which they change in a remarkable manner. 

 They are excessively pugnacious and predatory in their 

 habits, the larger species eating the smaller, and destroying 

 the eggs and fry of fishes to a prodigious extent. An 

 observer relates of the fifteen-spined stickleback, about six 

 inches in length, — sometimes called the " sea-adder,^' — " that 

 it keeps near rocks and stones clothed with sea-weeds, 

 among which it takes refuge upon any alarm. Though less 

 active than its brethern of the fresh water, it is scarcely less 

 rapacious. On one occasion I noticed a specimen engaged 

 in taking its prey from a clump of sea-weed, in doing which 

 it assumed every posture between the horizontal and 

 perpendicular, with the head downwards and upwards, 

 thrusting its projecting snout into the crevices of the stems, 

 and seizing its prey with a spring. Having taken this fish 

 with a net, and transferred it to a vessel of water, in company 

 with an eel three inches long, the latter was attacked and 

 devoured head foremost ; not, indeed, altogether, for the eel 

 was too large a morsel, so that the tail remained hanging out 

 of the mouth, and it was obliged to disgorge the eel partly 

 digested." 



A writer relates some interesting observations on the 

 fighting propensities of these animals when confined in a tub 

 of water : 



"A few at first are turned in, and swim about in a shoal, 

 apparently examining their new habitation. Suddenly one 

 will take possession of a corner of a tub, or, as it will 

 sometimes happen, of the bottom, and will instantly com- 

 mence an attack on its companions; and if any of these 

 venture to oppose its rule, a regular and most furious battle 

 ensues. The two combatants swim round and round each 



