THE FULL-ARMED STICKLEBACK. 195 



them gained, for a considerable time, four shillings a-day 

 by selling them at the rate of a halfpenny a bushel.* The 

 habits of these fish, when observed while under confinement, 

 are extremely pugnacious. " When a few were placed in 

 a wooden vessel, they swam about in a shoal, apparently 

 exploring their new habitation ; suddenly, one will take 

 possession of a particular corner of the tub, or, as it will 

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

 mence an attack upon his companions ; and if any one of 

 them ventures to oppose his sway, a regular and most fu- 

 rious battle ensues. The two combatants swim round and 

 round each other with the greatest rapidity, biting and en- 

 deavouring to pierce each other with their spines, which on 

 these occasions are projected. I have witnessed a battle of 

 this sort which lasted several minutes before either would 

 give way ; and when one does submit, imagination can 

 hardly conceive the vindictive fury of the conqueror, who, 

 in the most persevering and unrelenting way, chases his 

 rival from one part of the tub to another, until fairly ex- 

 hausted with fatigue. They also use their spines with such 

 fatal effect that, incredible as it may appear, I have seen 

 one during a battle absolutely rip his opponent quite open, 

 so that he sunk to the bottom and died. I have occasion- 

 ally known three or four parts of the tub taken possession 

 of by as many other little tyrants, who guard their territo- 

 ries with the strictest vigilance. These are the habits of 

 the male fish alone ; the females are quite pacific, appear 

 fat, as full of roe, and never assume the brilliant colours of 

 the male, by whom, as far as I have observed, they are un- 

 molested." t 



However plentiful this species may be on some parts of 



* Encyclopedia Britannica, article Ichthyology, 

 + YarrelPs British Fishes. 



N L X 



