FISHES. 



183 



sides; the head above is slightly curved, the jaws are armed with compressed and 

 trenchant teeth, but of rather small size, and the palate is toothless ; there are two 

 dorsal fins, one sustained by about eight weak spines, the second, as well as the anal, 

 long, and covered with scales ; the tail is powerful, the fin deeply einarginated, and the 

 vcntrals are thoracic and normal, having a spine and five rays each. 



The blue-fish {Potnatomus saltatrix), as it is generally called, rejoices in many 

 other names according to locality or condition. Blue-fish is that by which it is known 

 to by far the greatest number of people, and especially in the Middle and New Eng- 

 land states, but in Rhode Island it is called horse-mackerel ; it is the tailor of the 

 Philadelphia, Baltimore, and Washington markets ; in i)arts of Virginia and North 

 Carolina it is known as green-fish ; and south of Cape Hatteras the name changes to 

 skipjack. The young in New England are often distinguished as snapjiers, blue snap- 

 pers, and snajiping mackerel,' and in the vicinity of New York also as snapping mack- 

 erel, as well as white-fish. Some of these names are quite suggestive of the appearance 

 or habits of the tish. Blue merging into greenish is the color ; the teeth, though small, 

 are sharp and lancet-like, and snip like a tailor's shears, and this ])eculiarity was also 

 taken as the basis of a happy generic name ( Temnodon or cutting-teeth), by Cuvier, 



Fig. 110. — Pomatomus saliatri.i\ blue-tish. 



but, unfortunately, that name must be given up for the much earlier one Pomatomus ; 

 snapping describes the movements by which it takes its prey, and skip-jack alludes 

 both to its resemblance to the species of Caranx, and to the manner in which it often 

 skips through the water. The young are whitish, and have not yet obtained the 

 greenish-blue tints of maturity. 



In size, individuals vary considerably. Those taken in the spring, as a lule, average 

 much smaller than those obtained in the fall. About four pounds each may be con- 

 sidered as the medium size for the spring individuals about New York, while those 

 occurring at the same time along the southern coast rarely exceed two or three 

 ]jounds in weight. The largest summer specimens in fact, according to Professor 

 Baird, are "those found farther to the eastward, where they ai-e not unfrequently met 

 with weighing from ten to fifteen ])ounds, although this latter weight is quite unusual." 

 In the fall, however, the average size is much larger, and the schools tli.-it iiKikc their 

 a]ipearance in October on the northern coasts embrace many individuals of fnun ten 

 to fifteen pounds, and it has been supposed by Professor Baird to be " not improbable 

 that the difference between the first-mentioned average and the last repi-esents the in- 

 crease by their summer feeding." Much larger specimens than those indicated by 

 these figures may, however, occasionally be found, and, in the last century, individuals 

 api)ear to have been obtained weighing forty or fifty pounds in Vineyard Sound, .and, 

 according to one old observer, Zaccheus Macy, " thirty of them would till a barrel." 



