452 THE EEL FAMILY. 



one individual varying at least from 8,000,000 to 3,000,000, and 

 unlike the gadoids and other fish already described, all these 

 eggs appear to ripen at the same time. The consequence is 

 that there is an enormous distension of the ovaries and the 

 pressure upon the surrounding organs appears, at least in 

 confinement, to cause the death of the parent. The total 

 weight of the ripe ovaries may considerably exceed one-third of 

 the total weight of the fish ; in fact. Day records the death of 

 a female conger in the Southport aquarium, which weighed 

 15J lbs. and the ovaries weighed no less than 7 lbs. From 

 these and other facts it is assumed that the conger becomes 

 sexually mature, only once, and perishes upon or immediately 

 after the extrusion of the ova. Cunningham, experimenting 

 upon captive congers in the Plymouth Laboratory, has brought 

 additional evidence to bear upon this point, and he holds that 

 the fishes which died at sexual maturity had undergone a 

 peculiar degeneration of the tissues, involving a loss of teeth and 

 a softening of the bony structures. He claims that this takes 

 place to such an extent that, assuming a like phenomenon in a 

 state of nature, the fish would be in an unfit state for capturing 

 ' its prey and death by starvation would result. This may be so, 

 but experiments upon fish in a state of captivity are occasionally 

 misleading (see Chapter on Growth-Rate). 



The facts, however, seem to favour the hypothesis that the 

 conger reproduces but once, and dies shortly thereafter. A 

 similar fate is believed to overtake the eel. S. Miiller stated 

 that the river-lamprey dies whilst spawning, and A. Miiller 

 maintained the same for the little lamprey, whilst Panizza 

 observed that the sea-lamprey is brought up dead in numbers 

 immediately after the spawning-period. These facts, if such 

 they be, all strengthen the case for the conger ; on the other 

 hand, ripe congers are found to vary very much in size from 

 8 feet downwards quite apart from the sexual diversity in size. 



Little definite is known concerning the spawning-period of 

 the conger, indeed facts seem to point to an indefinite spawning- 

 season, ripe females being found at nearly every month of the 

 year. This, however, is largely conjectural. If such were really 

 the case it would form evidence in favour of expecting that the 



