Chap. XII. Fishes. 34 1 



u glowed with an internal incandescence." After the breeding- 

 season these colours all change, the throat and belly become of a 

 paler red, the back more green, and the glowing tints subside. 



With respect to the courtship of fishes, other cases have been 

 observed since the first edition of this book appeared, besides that 

 already given of the stickleback. Mr. W. S. Kent says that the 

 male of the Labrus mixtus, which, as we have seen, differs in 

 colour from the female, makes " a deep hollow in the sand of the 

 " tank, and then endeavours in the most persuasive manner to in- 

 11 duce a female of the same species to share it with him, swim- 

 " ming backwards and forwards between her and the completed 

 " nest, and plainly exhibiting the greatest anxiety for her to follow." 

 The males of Cantharus lineatus become, during the breeding- 

 season, of deep leaden-black ; they then retire from the shoal, and 

 excavate a hollow as a nest. "Each male now mounts vigilant 

 " guard over his respective hollow, and vigorously attacks and 

 '• drives away any other fish of the same sex. Towards his com- 

 " panions of the opposite sex his conduct is far different; many of 

 " the latter are now distended with spawn, and these he endeavours 

 " by all the meacs in his power to lure singly to his prepared 

 " hollow, and there to deposit the myriad ova with which they are 

 " laden, which he then protects and guards with the greatest care. 25 



A more striking case of courtship, as well as of display, by the 

 males of a Chinese Macropus has been given by M. Carbonnier, 

 who carefully observed these fishes under confinement. 27 The 

 males are most beautifully coloured, more so than the females. 

 During the breeding-season they contend for the possession of 

 the females; and, in the act of courtship, expand their fins, 

 which are spotted and ornamented with brightly coloured rays, 

 in the same manner, according to M. Carbonnier, as the peacock 

 They then also bound about the females with much vivacity, and 

 appear by " l'etalage de leurs vives couleurs chercher a attirer 

 " l'attention des femelles, lesquelles ne paraissaient indifferentes 

 " a ce manege, elles nageaient avec une niolle lenteur vers les 

 " males et semblaient se complaire dans leur voisinage." After 

 the male has won his bride, he makes a little disc of froth by 

 blowing air and mucus out of his mouth/* He then collects the 

 fertilised ova, dropped by the female, in his mouth ; and this 

 caused M. Carbonnier much alarm, as he thought that they were 

 going to be devoured. But the male soon deposits them in the 

 disc of froth, afterwards guarding them, repairing the froth, and 

 faking care of the young when hatched. I mention these par- 

 ticulars because, as we shall presently see, there are fishes, the 



«« 'Nature,' Mf.y, 1873, p. 25. 27 'Bull, de la Soc. dVAcclimat 



Paris, July 1869, and Jan. 1870, 



