FAMILY PLANIDE — PLATESSA. 297 
THE RUSTY FLAT-FISH. 
PLATESSA FERRUGINEA, 
PLATE XLUI. FIG. 155.— (STATE COLLECTION.) 
The Rusty Dab, Platessa ferruginea. Storer, Report on the Fishes of Massachusetts, p. 141. 
Characteristics. With numerous minute rusty spots over the body. Dextral. A series of 
four white distant rounded spots along the dorsal and abdominal outline. 
Length twelve to twenty inches. 
Description. Elliptical ; roughened by orbicular scales, which likewise cover the opercular 
plates. The scales are rounded about the middle of the body, smaller towards the abdomen 
and tail, and extend to the tips of the caudal rays; they extend far on and even beyond the 
eyes, and are furnished with from four to six denticles on their posterior edges ; beneath they 
are rounded, becoming pointed towards the tail, and destitute of denticulations. The lateral 
line curves shortly over the pectoral fin, and then proceeds in a straight line through the middle 
of the tail. The snout produced ; a strong bony ridge separates the narrow space between 
the orbits, curves upward and backward, and appears to form a continuation with the lateral 
line. Eyes large, approximated and prominent. A row of small blunt teeth in each jaw, 
almost obsolete on the colored side ; on the upper pharyngeals, they are arranged in three 
transverse rows on a disk on each side, each series consisting of from eight to twelve small 
incurved teeth on each side. Branchial aperture large, and the membrane dilated with six rays. 
The dorsal fin arises above the anterior portion of the orbit, and runs backward to within a 
short distance of the accessory caudal rays; the rays of this fin extend beyond the mem- 
brane, and its tips are white ; they are longest between the thirty-fifth and fiftieth rays. The 
pectorals nearly equidistant between the back and thorax, rounded ; the first three simple, the 
remainder branched ; on the uncolored side, they are all simple. Ventrals extending to the 
origin of the anal. The anal has a horizontal spine before it; its rays gradually increase in 
size to the twenty-fifth, when they as gradually diminish to the last, which is opposite to the 
termination of the.dorsal. Caudal rounded, with rays nearly three inches long; all, with the 
exception of the first on each side, branched. The membrane of all the fins exceedingly 
delicate and diaphanous ; the opercular membrane almost transparent. Ovary, in the speci- 
men before me, long and triangular, almost filling up the abdominal cavity, and extending to 
within three inches of the base of the caudal rays. No air-bladder nor ceca. 
Color, Head and body greenish, with numerous irregular, crowded, chocolate or rust-colored 
spots, giving a rusty hue to tie animal. These spots appear to be confined to the body alone, 
not extending over the fins. A series of four or five distant obscure rounded spots along the 
dorsal, and a similar series along the abdominal outline. When held up to the light, these 
spots are deep black, and the whole body pellucid. Beneath white, except the lower margins 
Fauna — Parr 4. 38 
