354 FISHES 



lantic off the west coast of Africa. Schmidt* however, found 

 that the identification was not correct. One specimen was taken 

 by Schmidt himself in 1904 on the Danish research steamer 

 Thor, to the west of the Faroes at the surface. Another was 

 taken by Mr. Holt in August of the same year off the west of 

 Ireland. In 1905 Schmidt took the investigation steamer Thor 

 southwards from the Hebrides to the Bay of Biscay, following 

 the course of the 500 fathom line, and fishing with large pelagic 

 nets from time to time. As he went south he obtained increas- 

 ing numbers of the larval eel until off the entrance of the 

 English Channel at the end of June, 49° 25' N., 12° 20' W. he 

 captured as many as seventy specimens in a two hours haul. 

 Further south in the Bay of Biscay, specimens became scarcer 

 and finally none were found. The chief spawning ground of 

 the eel therefore lies to the west of the Channel at depths be- 

 tween 500 and 700 fathoms. The larvae, however, do not live 

 at or near the bottom. Some were taken at the very surface, 

 but they were most abundant at a depth of 50 fathoms, ap- 

 proaching nearer to the surface at night. When placed in 

 vessels of sea- water with sand and mud at the bottom, they 

 showed no tendency to burrow, although they avoided the 

 light. They swam with eel-like undulatory movements of the 

 body. They were of glassy transparency, only the eyes having 

 a silvery appearance. With them were captured enormous 

 numbers of other pelagic creatures, most of them, like the eel 

 larva;, of glass-like transparency ; of other fish-larvae there were 

 the Leptocephalus of the conger, the larvae of Fierasfer, of the 

 angler, of a species of ling, of several species of Gadidae, and 

 of some Pleuronectidae ; of invertebrates, the most abundant 

 were pelagic Ascidians, especially Salpae, Crustacea and molluscs. 

 The occurrence of the Leptocephalus of the conger shows that 

 this species also probably migrates to depths of some hundreds 

 of fathoms in order to spawn, and this would make it still easier 

 to understand why the females fail to spawn in aquaria. 



On 31st August and 1st September a few other specimens of 

 the eel larva were taken between St. Kilda and Rockall which 

 were more advanced in their metamorphosis. In March and 

 April the young eels which have almost completed their meta- 

 morphosis, though still perfectly transparent (glass-eels, Plate 

 XXIX., 7), have been taken at the surface at night in the North 



