HISTORY OF THE FISHES OF MASSACHUSETTS. 431 
ACIPENSER OXYRINCHUS, “Mitchill. 
The Sharp-nosed Sturgeon. 
(Pedra XXXV. Fic. 4.) 
Acipenser Osyrinchus, Sharp- -nosed? Sturgeon, Miron., "Trans, Lit. and Phil. Soe. of N. , SETS 462. 
^ LrsUEUR, Trans. Amer. Phil. Soc., New Series, np 394. 
d disi P nosed Sturgeon, STORER, Report, p. 178.. 
“ eee ete * "` Drkar, Report, p. 346, pl. 58, fig. 189. ' 
T .* ,.. Ayres, Fishes of Brookhaven, L. I., Bost. Journ. Nat. Hist., 1v. p. 287. 
- * — LiNSLEY, Cat. of Fishes of Connection’, Amer. Journ. Science. 
* |... ©, STORER, Mem. Amer. Acad., New Series, 11. p. 499. 
A de zl Synopsis, p. 247. 
Color. Of a grayish- brown color above; silvery upon the inferior portion of the 
sides; white beneath. Pupils black, irides: yellow. 
Description. Body elongated, pentagonal. - Entire surface — excepting 
that occupied by five longitudinal rows of flattened plates, of the same structure 
as the covering of the head, but of a lighter color. The largest plates form the 
dorsal ridge; in younger specimens these. plates are compressed at their sides, and 
terminate above in strong, sharp, recurved spines; while in this the spines:on the 
dorsal ridge in some plates: are obsolete, and the whole crest a mere sharp edge, 
and are obvious only on a few of the plates; radiating lines are distinctly seen 
running from the centre of these scales to. their circumference; this row is com- 
posed of ten plates. In the specimen formerly described by me, measuring two 
feet and three inches in length, this row contained twelve plates. The first are 
the largest; that at the commencement of the dorsal fin by far the smallest; be- 
tween the dorsal and caudal fins are situated four plates. In the specimen de- 
scribed in my * Report" two quite small plates were seen just back of the dorsal, 
forming a pair; next to these a much larger one, and, lastly, an elongated one at 
the commencement of the caudal fin. 
A second row of bony plates, twenty-eight in number, placed obliquely, com- 
mences just back of the operculum, situated where the lateral line is usually ob- 
served in fishes, and is continued to the base of the tail; these plates are narrowed 
to a point at their upper extremities, obtuse at their lower extremities, widened in 
their centres, and, like the former, are crowned by spines, more or less prominent, 
from the bases of which radii diverge. The posterior plates are much the smaller. 
Beneath this row,’ just back of the pectorals, commences a third row of plates, 
eight in number, placed vertically, larger than those of the last row. 
The head is flattened above, slightly depressed between the eyes, and terminates 
