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It results therefore from our investigations, that the commonly accepted explanation 

 of the apparent lack of eel larvae near the coast of North and West Europe, namely, 

 that they live buried in the ground in great depths and thus escape the fishing apparatus, 

 cannot be maintained. As in shown in all their characters they are true pelagic deep- 

 sea forms. As I often had occasion to examine specimens in the living condition, I 

 resolved nevertheless to test by direct experiment what their supposed ability to bury 

 themselves in the bottom amounted to. Several beakers with a mixture of mud and sand 

 on the bottom were filled with sea-water and a number of active and strong specimens 

 of L. brevifosin's were placed in them. Though the Leptocephali were very full of life 

 and swam about in the water they showed not the slightest tendency to desire to 

 bury themselves in the bottom. On the other hand experiments with different spe- 

 cimens of Z. brevirostris repeated over several days showed that they are shy to light, 

 constantly moving away from the lighted part of the beaker to where it was dark. 

 They were swimming with eel-like wavy movements of the body. If they were poked 

 at with a stick they often rolled themselves up into a circle and remained thus for some 

 time quiet in the water. As they were quite transparent and glass-clear in the living con- 

 dition, little more of them could be seen than the silvery eyes especially when they kept 

 still. It was likewise often of considerable difficulty, to distinguish them amongst the 

 enormous masses of glass-clear invertebrates, which were brought up with them in the 

 young-fish trawl. Some impression of these masses may be gained from the statement 

 that the contents of a single 2 hours haul (with 300 meters wire out) could fill over 650 

 liters. The chief inhabitants of this rich deep-sea fauna, of which Leptocephalus brevi- 

 rostris formed part, were large Sal pa e {Salpa fiisiforniis and zonaria), Dolioltim, 

 DiphyeSy large transparent Amphipods of the genus fhronima living in transparent barrel- 

 like bells, the large likewise transparent Pteropod Cymbiilia as well as several other 

 Pteropods, the peculiar large Heteropod Carinaria, thus all large transparent organisms 

 like the Leptocephali. Of fish young that occurred with the eel larvae, there should first 

 of all be mentioned the Leptocephalus of the conger {Lepiocephalus morrisii) and 4 

 other Leptocephali, the young of Fierasfer^ Lophitis, Molva birkelange^ Gadus pott- 

 tassoît^ Gadicnhts argenietis, Zeugopteriis megastoina and spp., a characteristic, plump 

 pelagic gadoid {Gargilius sp., Ad. Jensen nov. gen. & spec.) Macritriis species, many 

 different Scopelini etc. as well as adult specimens, some with eggs, of the needle fish 

 Neropliis pelagica and its young. All these forms are true warm-water species of the 

 Atlantic, most of which were not found during our investigations further north in the 

 Atlantic. They clearlj? belong mainly to the more southerly, warmer water-masses than 

 those we had previously investigated with the "Thor", even though single specimens of 

 some of them were found by us further north (west of the Faeroes and south of Iceland). 



The September-specimens deserve some special mention. As mentioned they 

 were all taken at a place to the west of St. Kilda almost at the same spot as we had 

 taken the first Leptocephali in June (57°46' N., 9°55' W.). The depth varied from 1030— 

 1310 meters. Essentially the same invertebrates accompanied the Leptocephali as in June, 

 but their quantity was generally much smaller (-/j — a few liters per 2 hours haul in 

 place of 10 — 20— 50— -100— even several hundreds in June). Essentially the same species 



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