FISHES OF THE GULF OF MAINE 



113 



Figure 49. — Thread herring (Opisthonema oglinum). Drawing by Louella E. Cable. 



fresh and brackish waters farther south in this 

 respect, but the two differ rather conspicuously in 

 various details. In the thread herring, the upper 

 edge of the tail fin is about 1% times as long as the 

 head (only about as long as the head in the 

 gizzard shad); the point of origin of the dorsal fin 

 is a little in front of the origin of the ventral fins 

 (a little behind in the gizzard shad); the distance 

 from the origin of the ventrals to the origin of the 

 anal fin is at least 1% times as long as the base of 

 the anal (only about % to % in the gizzard shad); 

 and the anal fin is very low, with its first few rays 

 a little shorter than the eye (about 1% times as 

 long as the eye in the "gizzard"). There is no 

 danger of confusing a thread herring with a young 

 tarpon with which it shares the prolonged dorsal 

 ray, for its dorsal fin originates in front of the 

 ventrals, while the two fish are far apart in general 

 appearance. This is a rather thin fish, its body 

 about 2% to 3 times as long (to the base of the tail) 

 as deep ; the belly is sharp and saw edged ; the tail 

 deeply forked as in our other herrings. There are 

 18 to 19 rays in the dorsal fin, 22 to 24 in the anal. 



Color. — Bluish above, silvery on sides and belly. 

 The scales along the back have dark centers, form- 

 ing longitudinal streaks, and there is a faint dark 

 spot just behind the upper margin of the gill 

 cover; the dorsal and caudal fins have black tips. 



Size. — Maximum length about 12 inches. 



General range. — Atlantic coast of America in 

 tropical and subtropical latitudes, south to 

 Brazil, straying northward to Chesapeake Bay, 

 and occasionally as far as southern Massachusetts. 



Occurrence in the Gulf of Maine. — A thread 

 herring is caught off southern New England 

 occasionally; they were even reported as rather 



common in Buzzards Bay and in Vineyard Sound 

 during the summer of 1SS5. But there is only one 

 record of it within the Gulf of Maine, a single 

 specimen 7 inches long, taken off Monomoy Point, 

 at the southern angle of Cape Cod, in August 

 1931. 25 Being a tropical fish, it is not apt to 

 reach the Gulf except as the rarest of strays. 



Menhaden Brevoortia tyrannus (Latrobe) 1802 

 Pogy; Mossbunker; Fat back 



Jordan and Evermann, 1896-1900, p. 433. 



Description. — This fish is universally called 

 "pogy" in the Gulf of Maine but no less than 30 

 common names are in use south of Cape Cod. It 

 is flattened sidewise like all our other herrings, 

 has a sharp-edged belly, and is as deep proportion- 

 ally as the shad (body about 3 times as deep as 

 long), though the general form is altered when the 

 fish are fat. The very large scaleless head, which 

 occupies nearly one-third of the total length of the 

 body, gives the menhaden an appearance so dis- 

 tinctive that it is not apt to be mistaken for any 

 other Gulf of Maine fish. It is likewise distin- 

 guishable from all its local relatives by the fact that 

 the rear margins of the scales are nearly vertical 

 (not rounded), and are edged with long comblike 

 teeth instead of being smooth. The dorsal fin 

 originates over the ventrals or very slightly 

 behind them. We need only point out further 

 that the pogy is toothless, its tail deeply forked, 

 its ventral fins very small, its dorsal and anal of 

 moderate size, its mouth large and gaping back as 

 far as the hind margin of the eye, and that the tip 

 of its lower jaw projects beyond the upper. 



» Reported by Mactoy, Bull. Boston Soc. Nat. Hist., No. 61, 1931, p. 21. 



