88 BULLETIN OF THE BUREAU OF FISHERIES 



The conger is an extremely prolific fish, the number of eggs a female may produce 

 having been estimated as high as from 3 to 6 millions. Conger eggs have never been 

 identified with absolute certainty, but a considerable number of large pelagic eggs 

 towed by the Grampus (presumably on the surface) over the tilefish grounds 30 

 miles south of Nantucket lightship on July 31, 1900, probably belonged to this 

 species, the larvae hatched from them undoubtedly being eels while the eggs them- 

 selves were as certainly not those of the common eel. These eggs (fig. 36b) were 

 2.4 to 2.75 mm. in diameter with 1 to 6 oil globules, one invariably much larger than 

 the others. They hatched in from two to three days in the Woods Hole hatchery, 

 suggesting a total incubation period of four to five days at the prevailing summer 

 temperature. 



It has long been known that the conger, like the common eel, passes through 

 a peculiar ribbonlike larval stage — the so-called "leptocephalus" stage — very broad 

 and thin and perfectly transparent, with a very small head. In fact the first 

 "leptocephalus" ever seen (about 1763) was the larval conger, but although its 

 true identity was suspected it was not until 1S86, when the famous French zoologist, 

 Delage, 76 actually reared one through its metamorphosis at the biological station 

 at Roscoff, that the identity of this larva was definitely established. The lep- 

 tocephalus of the conger is relatively more slender than that of the common eel, and 

 it can always be identified (under a lens) by the fact that its vertebrae and muscle 

 segments are far more numerous (153 to 159 or more, as against only about 107 in 

 the American eel and about 114 in the European eel), and that they grow to a 

 length of 150 to 160 mm. 



The duration of the larval period of the conger is not known. The process of 

 metamorphosis consists essentially in a thickening and narrowing of the body, an 

 enlargement of the head, the formation of the swim bladder and the permanent 

 teeth, and the pigmentation of the skin, a change that occupied about two months 

 (May to July) in the case of Delage's specimen. At its completion his young 

 conger was 9.3 centimeters (3.6 inches) long. 77 



36. Snipe eel (Nemichthys scolopacem Richardson) 



Jordan and Evermann, 1896-1900, p. 369. 



Description. — The snipe eel is made easily recognizable by its extremely slender 

 body (the fish may be 75 times as long as deep), with its tail tapering to a thread, 

 and by its bill-like jaws, which are equally elongate, the upper one curving upward 

 but the lower nearly straight. The head is much deeper than the neck, with a 

 large eye. The dorsal fin originates in front of the pectoral, the anal about 

 abreast of the tip of the latter, and both run back to the tip of the tail. There 

 has been some confusion in the published accounts and illustrations as to these two 

 fins, for while Vaillant 78 shows both about as high throughout their length as the 



78 Comptes Rendus hebdomadaires des stances de l'Academie des Sciences, vol. 103, 1886, p. 698. Paris. 



" Schmidtlein (Mittbeilungen aus der Zoologisehen Station zu Neapel, Band I, 1879, p. 135) speaks of young "congers" at 

 Naples in April as hardly one-third as long as this, a discrepancy suggesting that they may actually have belonged to one of the 

 Murfenoid eels. 



'• Poissons. Expeditions Scientifiques du Travailleur et du Talisman, Pendant les Annees 1880, 1881, 1882, 1883 (1888), PI. 

 VII, figs. 2 and 2a. Paris. 



