Chap. XII. 



Fishes. 



337 



" their mates." " The young males resemble the adult females 

 in structure and colour. Throughout the genus Callionymus," 

 the male is generally much more brightly spotted than the 

 female, and iu several species, not only the dorsal, but the anal 

 fin is much elongated in the males. 



The male of the Cottus scorpius, or sea-scorpion, is slenderer 

 and smaller than the female. There is also a great difference 

 in colour between them. It is difficult, as Mr. Lloyd " remarks, 

 " for any one, who has not seen this fish during the spawning- 

 " season, when its hues are brightest, to conceive the admixture 

 " of brilliaut colours with which it, in other respects so ill- 

 " favoured, is at that time adorned." Both sexes of the Labrus 

 mixtus, although very different in colour, are beautiful; the 

 male being orange with bright blue stripes, and the female 

 bright red with some black spots on the back. 





ikjwieEJ 



^■W^^mm 



■^-^" 



Fig. 30. Xiphophorus HtUerli. Upper figure, male ; lower figure, female. 



In the very distinct family of the Cyprinodontidse— inhabitants 

 of the fresh waters of foreign lands— the sexes sometimes differ 

 much in various characters. In the male of the Mollienesia 

 petenensis,'^^ the dorsal fin is greatly developed and is marked 



'3 'NatrnV July 1873, p. 264. 



■* ' Catalogue of Acanth. Fishes 

 in the British Museum,' by Dr. 

 Giinther, 1861, pp. 138-151. 



'^ ' Game Birds of Sweden,' &c.. 

 1867, p. 466 



23 



'« With respect to this and the 

 following species I am indebted to 

 Dr. Giinther for information : see 

 also his paper on the 'Fishes of 

 Central America,' in 'Transact. 

 Zoolog. Soc' vol. vi. 1868, p. 485. 



