FISHES OF CHESAPEAKE BAY 
171 
Comparison of lengths and weights of P. americanus 
Length, in millimeters 
Number 
of speci- 
mens 
Average 
length, 
in inches 
Average 
weight, 
in ounces 
Length, in millimeters 
Number 
of speci- 
mens 
Average 
length, 
in inches 
Average 
weight, 
in ounces 
110-129 
14 
4. 7 
0. 6 
265 
1 
10. 2 
7.7 
130-149 
10 
5. 5 
1. 0 
290 
1 
11.0 
10.2 
150-169 
12 
6. 3 
1. 5 
305 
1 
11.8 
13.8 
170-189 
2 
7. 1 
2. 4 
370 
1 
16.0 
20.0 
220 
i 
8.6 
5.0 
61. Genus LOPHOPSETTA Gill. Sand flounders 
Body broad, much compressed, translucent; eyes and color on the left side; mouth large; 
maxillary reaching opposite the pupil; lateral line with a high arch anteriorly; scales small, cycloid; 
dorsal fin beginning in front of eye, the anterior rays long, distally free and branched; ventral fins 
dissimilar in shape and position, broad at base, the left one inserted on ridge of abdomen. This 
genus consists of a single species. 
80. Lophopsetta maculata (Mitchill). Sand flounder; Window-pane; Spotted flounder; Sand dab. 
Pleuronectes maculatus Mitchill, Rept., Fish., New York, 1811, p. 9; New York. 
Lophopsetta maculata Jordan anrl Evermann, 1S96-1900, p. 2660, PI. CCCLXXXII, fig. 938. 
Bothus maculatus Bean, 1891, p. 85. 
Head 2.9 to 4.05; depth 1.45 to 1.8; D. 63 to 69; A. 46 to 52; scales 92 to 102. Body rhomboid, 
very strongly compressed; head rather small; snout short, 3.7 to 4.45 in head; eye 2.7 to 3.95; 
interorbital narrower than eye, proportionately much broader in adult than in young, 1.8 to 3.5 in 
eye; mouth nearly vertical; lower jaw projecting, with a bony knob at chin; maxillary broad, reach- 
ing below middle of lower eye, 2 to 2.45 in head; teeth in jaws small, in a single series laterally, in 
a band anteriorly; gill rakers slender, 24 to 26 on lower limb of first arch; lateral line with a prominent 
arch anteriorly, shorter than head; scales small, scarcely imbricate; origin of dorsal nearer tip of 
snout than eye, the anterior rays distally free and branched; caudal fin round; origin of anal between 
base of ventrals; ventral fins small with broad bases, the left one nearly on ridge of abdomen; 
pectoral fins moderate, the left one somewhat larger than the right, 1.25 to 1.65 in head. 
Color light brown mottled with numerous lighter brown and black spots, these spots extend- 
ing on the vertical fins, where they sometimes become elongate; white below. Some specimens are 
much darker than others but the pattern is about the same. 
Many specimens, ranging in length from 40 to 260 millimeters (1 % to 10J4 inches), were 
preserved. The young do not differ greatly from the adults. The sand flounder is recognized by 
the ventral fins, which are broad at the base and dissimilar in shape and position. These characters, 
in combination with the strongly arched lateral line and the free and branched rays forming the 
anterior part of the dorsal fin, distinguish this flounder from all others known from Chesapeake Bay. 
We have nothing new to add concerning the food of this flounder. It is known to feed freely 
on fish of suitable size and on crustaceans, certain mollusks, annelids, and ascidians. 
Spawning, according to Bigelow and Welsh (1925, p. 520), takes place in late spring and summer 
in the Gulf of Maine. It seems probable that spawning takes place much earlier in Chesapeake 
Bay, as fish with fairly well developed gonads were taken as early as the latter part of September. 
The larval development is said to be rapid. Tracy (1910, p. 166) gives a length of 2 to 3 inches for 
the young in July and 4 inches or more by December in Rhode Island waters. 
The eggs are spherical, transparent, buoyant, and 1 to 1.08 millimeters in diameter. Incuba- 
tion requires about eight days at 51° to 56° (Bigelow and Welsh, 1925, p. 520). The development 
of the larvse is rapid, and at 10 millimeters the migration of the eye is completed and the fry are 
ready to take to the bottom (Williams, 1902, p. 2). 
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