THE LARVA OF THE EEL. 285 
in other places from its habit of hiding or burrowing in the sea 
bottom. In captivity the larva of the conger was found to hide 
at the bottom and avoid the light. JL. Kefersteini, the larva of 
Ophichthys serpens, lived in the aquarium buried in the sand; and 
the larva of Congromurxna balearica also burrowed into the sand, 
although, singularly enough, it could only be kept alive on a naked 
marble bottom. We are not told whether these larvae came out at 
night and swam about freely. That the larvee of the conger and 
common eel are not constantly pelagic at night seems proved by the 
fact that they have never been taken in abundance in nocturnal 
tow-netting expeditions. I conclude, therefore, that these Lepto- 
cephali, and all those known from the Mediterranean, are not truly 
pelagic, but live on or in the sea bottom, and that the reason they 
are found in the open water or at the surface at Messina is that 
there the strong tidal currents and eddies stir up the bottom and 
carry their hght bodies about as scraps of paper are lifted and borne 
along by the wind. Reference to my previous paper, and the records 
which are there cited, will show that in two cases D. Morrisit has 
been taken in a hand-net near the surface of the water, but in other 
cases it was taken from the bottom,—for instance, in the process of 
fishing for prawns. ‘There can be little doubt that the larvee of the 
conger and of the eel exist around our coasts in great abundance, 
under stones or buried in sand or gravel, and that we do not catch 
them because we do not know the right way to go about it. 
But, on the other hand, we find constantly in narratives of oceanic 
zoological researches that Leptocephali were taken in abundance in 
ordinary tow-nets worked near the surface. This, it is to be 
remarked, occurs always in the tropics. For instance Giglioli and 
Issel, in their volume Pelagos, published in 1884, state that twice 
only during the vovage of the ‘‘ Magenta” they found specimens of 
Leptocephalus in the pelagic net, once in sight of Java, once in the 
South Pacific. 
In the ‘‘ Challenger”’ narrative the occurrence of pelagic Lepto- 
cephali is only mentioned twice, once in the account of pelagic 
animals observed between [Fernando Noronha and Bahia, off the 
coast of Brazil, 5° to 15° south latitude, the second time among 
those captured on the voyage from the New Hebrides to New York, 
in about the same latitude to the eastward of Australia in the Pacific. 
In the former case the Leptocephali were accompanied by the Pleuro- 
nectid larva of Rhomboidichthys, the larva originally known as 
Plagusia, characterised by the peculharity that the lower eye reaches 
the upper surface by passing through the base of the dorsal fin. Dr. 
Giinther gives the following account of the Leptocephali in his 
Report on the Pelagic Fishes of the ‘ Challenger.” He says that 
5) 
