78 BULLETIN OF THE BUREAU OF FISHERIES 



like mouth of the first two separates them at a glance from the true eels, while in all 

 the rest either there is a well-marked separation between anal and caudal fins, 

 ventral fins (large or small) are present, or the dorsal fin is spiny, not soft. 



Only four true eels are known from the Gulf of Maine: The common eel (p. 78), 

 the slime eel (p. 83), the conger (p. 86), and the snipe eel (p. 88), which fall into four 

 different families according to American usage. Most European students, however, 

 put the first three (with many other species) into one family (the Anguillidse) , and 

 the snipe eel and its relatives in a second (the Nemicthyida?) . A fifth species, the 

 long-nosed eel (a deep-water form), is to be expected in the deepest parts of the Gulf 

 though it has not been recorded there as yet. The group likewise includes the trop- 

 ical morays and sundry deep-sea forms, some of them exceedingly bizarre in 

 appearance. 



Common, conger, and slime eels look much alike, but are separated from one 

 another by the size of the mouth and by the relative lengths of the fins. In the snipe 

 eels the two jaws are prolonged into a very long slender beak, recalling that of a 

 silver gar, the tail is whiplike, the neck noticeably slimmer than the head, and the 

 general form extremely slender. 



KEY TO GULF OF MAINE EELS 



1. Both jaws are prolonged into a long slender bill Snipe eel, p. 88 



The jaws are not bill-like, the snout being short and blunt 2 



2. The anal fin originates well in front of the point of origin of the dorsal Long-nosed eel, p. 84 



The anal fin originates behind the point of origin of the dorsal 3 



3. The dorsal fin originates far behind the tip of the pectoral Common eel, p. 78 



The dorsal fin originates close behind the tip of the pectoral 4 



4. Mouth large, gaping back as far as the middle of the eye; very strong and active 



Conger, p. 86 



Mouth small, falling short of the eye; soft, slimy, and feeble Slime eel, p. 83 



32. Eel (Anguilla rostrata LeSueur) 



American eel; Common eel; Silver eel; Fresh- water eel 



Jordan and Evermann (A. chrysypa Rafinesque), 1896-1900, p. 348. 



Description. — In the common American eel the dorsal fin originates far behind 

 the pectoral, this character being of itself a sufficient field mark to distinguish it 

 from the conger, from which it also differs in that the lower jaw projects beyond the 

 upper or at least equals it in length, and that its eyes are small and round. Further- 

 more, it develops scales after it is about 3 or 4 years old, though these are so small 

 that they might be overlooked. Like the conger, however, it has a pointed snout, 

 a large mouth gaping back to or past the middle of the eye, and gill slits set horizontal 

 on the sides of the neck, their upper corners abreast of the center of the base of the 

 pectoral fin. It is very closely related to the European eel (Anguilla vulgaris), 

 but has fewer vertebras (about 107 as compared with about 114 or 115). 



Size. — Eels are said to grow to 4 feet in length and to 16J^ pounds in weight. 

 Full-grown females average only about 2 to Z}4, feet, however, and males are 

 smaller. Any eel more than 18 inches long would probably be a female, and one 

 more than 24 inches in length would certainly be one. 



