FISHES 187 



ing 50 lbs. and upwards are not uncommon. This refers to 

 specimens captured in the sea. Eipe males have frequently 

 been obtained by keeping specimens alive in aquaria, but the 

 females always die before they are quite ripe. The weight 

 of such nearly ripe females after death is much less than the 

 weight of large specimens newly captured, and this is not 

 surprising when we consider that the female in the aquarium 

 takes no food when her ovaries begin to ripen, and continues 

 to fast for about six months before she dies. The weights of 

 gravid females, examined at the Plymouth Laboratory, varied 

 from 16 lbs. to 33 lbs. ; the lengths from 4 feet 6 inches to 

 5 feet 4 inches. 



The ripe male in the aquarium was observed to differ from 

 the young female in three slight peculiarities : (1) the snout 

 was blunter and flatter ; (2) the eyes appeared larger in pro- 

 portion to the head ; (3) the ventral surface was somewhat 

 pigmented. 1 



It is difficult to offer any explanation of the small 

 size of the male conger. The testes are not small in 

 proportion to the body as in the male sole, on the contrary 

 when ripe they distend the body cavity, as in the case of the 

 male herring. It is easy to argue that the large size of the 

 female is necessary to supply nourishment to the immense 

 number of ova which she produces, but that does not show 

 what conditions of life and growth have given rise to the 

 difference of size between the sexes. It is possible, though 

 not yet proved, that the difference is not so much rate of 

 growth, as time of growth, the male becoming mature at an 

 early age. The male salmon is known to become mature 

 sometimes when only a few inches long ; but then he grows 

 afterwards, while the conger, whether male or female, ceases 

 to grow when the generative organs begin to mature, and dies 



1 Cunningham, "Reproduction and Development of the Conger," Journ. 

 Mar. Biol, Assoc, vol. ii. 1892. 



