86 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



9. 



The upper outline of the forward part of the lower jaw (visible if mouth is opened) is nearly straight, ana does not show 



a pronounced angle; the upper jaw extends back about level with the rear edge of the eye Shad, p. 108 



The upper outline of the forward part of the lower jaw is concave with a pronounced angle; the upper jaw reaches 



back only about to the level of the center of the eye 9 



Breadth of eye is greater than distance from front of eye to tip of snout; back distinctly grey green; lining of belly 



cavity pale grey Alewife, p. 101 



Breadth of eye is only about as great as distance from front of eye to tip of snout; back distinctly blue green; lining 



of belly cavity sooty or black Blue back, p. 106 



Ten pounder EIojjs saitrus Linnaeus 1766 

 Jordan and Evermann, 1896-1900, p. 410. 



Description. — The ten pounder is herring-like in 

 the arrangement of its fins, with the single and 

 soft-rayed dorsal fin originating about midway 

 along its back; in having no adipose fin; in the 

 position of its ventral fins about midway between 

 tip of snout and fork of tail ; and in its forked-tail 

 fin. But its scales are very much smaller relatively 

 than those of any of our herrings, and its mouth 

 is much larger, with the upper jawbone extending 

 rearward considerably beyond the rear edge of the 

 eye. Being about one-sixth as deep as it is 

 long, it is a much more slender fish than any of 

 our herrings except the round herring, and its 

 belly is rounded like that of the latter. But its 

 trunk is more flattened sidewise than that of the 

 round herring, its dorsal fin-origin is over the ven- 

 trals (well in advance of the ventrals in the round 

 herring), and its tail fin is much wider relatively 

 than that of any herring, and more deeply forked. 



A more important structural character is that 

 its tliroat is stiffened between the branches of its 

 lower jaw by a long bony plate, which it shares 

 with the tarpon, but which no member of the her- 

 ring tribe has. Its closest affinity among fishes 

 yet known from our Gulf is with the tarpon. But 

 its scales are very much smaller than those of the 



latter, nor does its dorsal fin have the prolonged 

 ray characteristic of the tarpon. 



Color. — Silvery all over, with the back bluish, 

 the lower parts of the sides and the lower surface 

 yellowish; the dorsal and caudal fins dusky yellow- 

 ish and silvery; the ventral and pectoral fins 

 yellowish speckled and dusky. 



Size. — The ten pounder is said to grow to a 

 length of 3 feet, 12 but few of those caught are 

 longer than about 20 inches. 



General range. — Atlantic coast of America, from 

 Brazil northward; commonly to North Carolina, 

 in small numbers and less regularly to southern 

 New England, and perhaps straying around the 

 elbow of Cape Cod on rare occasions. The ten 

 pounder of our Atlantic coast is represented in 

 tropical-warm temperate seas in various other 

 parts of the world by relatives so close that they 

 may all finally prove to represent only the one 

 wide-ranging species. 13 Our only reason for men- 

 tioning this southern fish is that one reported as 

 from Chatham, Mass., may have been taken on 

 the Gulf of Maine shore of Cape Cod. H Ten 

 pounders are taken from time to time near Woods 

 Hole. 



u Jordan and Evermann. Bull. 47. U. S. Nat. Mas., Pt. 1, 1896, p. 410. 



» Smith (Sea Fishes Southern Africa, 1949, p. 86) considers this probable. 



» This specimen, taken on October 19, 1888, and reported by Bigelow and 



Schroeder (Copeia, 1940. p. 139) is in the Museum of Comparative Zoology. 



Figure 38. — Ten pounder (Elops saurus), Massachusetts. From Goode. Drawing by H. L. Todd. 



