THE CONGER EEL i8i 



It is possible that subsequent investigations may confirm Mr 

 Cunningham's singular proposition ; but it is certain that he 

 argues somewhat boldly from the particular case of the aquarium 

 to the general case of nature. The Plymouth tank-house, at 

 which he pursued his studies, is admirable of its kind, and 

 even the hypercritical could scarcely express anything but 

 appreciation of the manner in which it is conducted. Yet not 

 the Director himself would probably claim that it accurately 

 reproduces the varied conditions of food and temperature that 

 obtain even within the Sound, just outside its walls ; and indeed 

 the Sound itself may be quite inadequate to the requirements 

 of spawning conger. The same naturalist has, for instance, 

 made some very interesting studies of the rate of growth of 

 different fishes in the same tanks ; but his results would 

 almost certainly call for considerable modification if they had 

 to be reconciled to those obtaining under perfectly natural 

 conditions. Even the spawning-season in captivity differs 

 appreciably from that observed in the open sea. The obser- 

 vations made in such an aquarium as that at Plymouth must 

 always be interesting, and may often be valuable, but they 

 must, to be of use, be interpreted with due allowance for the 

 influence of artificial environment. It has been observed, for 

 instance, that congers in the Brighton Aquarium, fed on alter- 

 nate days only, have come to know the feeding-time and to 

 display no activity whatever on the intervening fast-days. 

 This, while of interest, no doubt, to the student of animal 

 intelligence, chiefly illustrates the extent to which artificial 

 conditions may modify the natural habits of captive fishes. 



Let us for a moment examine Mr. Cunningham's data and 

 arguments in favour of this theory of the conger dying after 

 its first spawning. To what, after all, do they amount .'' 



He has never known a female to spawn in captivity, the 

 nearest approach to this episode having been the death of a 

 ripe female unable to deposit the eggs. He also admits that 

 ripe conger are never obtained from the sea, owing apparently 



