328 THE DESCENT OF MAN. 



scales, by the aid of which two males, one on each side, hold the 

 female, whilst she runs with great swiftness on the sandy beach, 

 and there deposits her spawn." The widely distinct Monacanthus 

 scopas presents a somewhat analogous structure. The male, as 

 Dr. Giinther informs me, has a cluster of stiff, straight spines, 

 like those of a comb, on the sides of the tail; and these in a 

 specimen six inches long were nearly one and a half inches in 

 length; the female has in the same place a cluster of bristles, 

 which may be compared with those of a tooth-brush. In another 

 species, M. peronii, the male has a brush like that possessed by 

 the female of the last species, whilst the sides of the tail in the 

 female are smooth. In some other species of the same genus the 

 tail can be perceived to be a little roughened in the male and per- 

 fectly smooth in the female; and lastly in others, both sexes have 

 smooth sides. 



The males of many fish fight for the possession of the females. 

 Thus the male stickleback (Gasterosteus leiurus) has been de- 

 scribed as "mad with delight," when the female comes out of her 

 hiding-place and surveys the nest which he has made for her. 

 "He darts round her in every direction, then to his accumulated 

 "materials for the nest, then back again in an instant; and as 

 "she does not advance he endeavors to push her with his snout, 

 "and then tries to pull her by the tall and side spine to the nest."" 



The males are said to be polygamlsts;' they are extraordinarily 

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

 battles are at times desperate; "for these puny combatants 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 fight- 

 ing swim round and round each other, biting and endeavoring to 

 pierce each other with their raised lateral spines. The same 

 writer adds,'* "the bite of these little furies is very severe. They 

 "also use their lateral spines with such fatal effect, that I 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 con- 

 quered, "his gallant bearing forsakes him; his gay colors fade 

 "away; and he hides his disgrace among his peaceable compan- 

 "ions, 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. Giinther. Mr. Shaw 



- 'The American Naturalist,' April, 1871, p. 119. 



3 See Mr. R. Warington's Interesting articles in 'Annals and Mag. of 

 Nat. Hist.' Oct. 1S52, and Nov., 1SB5. 

 * Noel Humphreys, 'River Gardens,' 1857. 

 5 Loudon's 'Mag. of Nat. History,' vol. iii. 1830, p. 331. 



