332 lite Descent of Man. Part I L 



The males are said to be polygamists ; 4 they are extraordinarily 

 bold and pugnacious, whilst " the females are quite pacific." 

 Their battles are at times desperate ; " for these puny com- 

 " batants fasten tight on each other for several seconds, tumbling 

 " over and over again, until their strength appears completely 

 " exhausted." With the rough-tailed stickleback (G. trachurus) 

 the males whilst fighting swim round and round each other, 

 biting and endeavouring to pierce each other with their raised 

 lateral spines. The same writer adds, 5 " the bite of these little 

 " furies is very severe. They also use their lateral spines with 

 " such fatal effect, that 1 have seen one during a battle absolutely 

 " rip his opponent quite open, so that he sank to the bottom and 

 " died." When a fish is conquered, " his gallant bearing forsakes 

 " him ; his gay colours fade away ; and he hides his disgrace 

 ''among his peaceable companions, but is for some time the 

 " constant object of his conqueror's persecution." 



The male salmon is as pugnacious as the little stickleback ; 

 and so is the male trout, as I hear from Dr. Gunther. Mr. Shaw 

 saw a violent contest between two male salmon which lasted 

 the whole day ; and Mr. R. Buist, Superintendent of Fisheries, 

 informs me that he has often watched from the bridge at Perth 

 the males driving away their rivals, whilst the females were 

 spawning. The males " are constantly fighting and tearing each 

 " other on the spawning-beds, and many so injure each other as 

 " to cause the death of numbers, many being seen swimming near 

 " the banks of the river in a state of exhaustion, and apparently 

 " in a dying state." 6 Mr. Buist informs me, that in June 1868 

 the keeper of the Stormontfield breeding-ponds visited the 

 northern Tyne and found about 300 dead salmon, all of which 

 with one exception were males ; and he was convinced that they 

 had lost their lives by fighting. 



The most curious point about the male salmon is that during 

 the breeding-season, besides a slight change in colour, " the 

 *' lower jaw elongates, and a cartilaginous projection turns 

 ' l upwards from the point, which, when the jaws are closed, 

 ' occupies a deep cavity between the intermaxillary bones of the 

 upper jaw." 7 (Figs. 27 and 28.) In our salmon this change of 

 structure lasts only during the breeding- season ; but in the 



4 Noel Humphreys, 'River Gar- experienced observer (Scrope's ' Days 

 dens,' 1857. of Salmon Fishing,' p. 60) remarks 



5 Loudon's ' Mag. of Nat. History,' that like the stag, the male would, 

 vol. iii. 1830, p. 331. if he could, keep all other males 



6 'The Field,' June 29th, 1807. away. 



For "Mr. Shaw's statement, see 7 Yarrell, ' History of British 



'Edinburgh Review,' .1843. Another Fishes,' vol. ii. 1836, p. 10, 



