276 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



Winter flounder Pseudopleuronectes americanus 

 (Walbaum) 1792 



Blackback; Georges Bank flounder; Lemon 

 sole; Flounder; Sole; Flatfish; Rough 

 flounder; Mud dab; Black flounder 



Jordan and Evermann, 1896-1900, p. 2647. 



Description.- — This is a small-mouthed, right- 

 handed species (eyes on the right side and viscera 

 on the right). But it is easily separable from the 

 yellowtail, which is similarly characterized, by 

 the fact that its lateral line is nearly straight 

 (at most only slightly bowed abreast the pectoral 

 fin); that the dorsal profile of its head is less 

 concave; that its nose is blunter; that its eyes 

 are farther apart; that it has fewer fin rays; and 

 that its fins are less tapering in outline. The 

 most obvious differences between the winter 

 flounder and the smooth flounder (p. 283) is that 

 the former is rough scaled between the eyes, the 

 latter smooth there, and that the winter flounder 

 has the larger number of anal fin rays. On the 

 other hand, it has only about two-thirds as many 

 dorsal rays as the witch (p. 285) ; it lacks the mucous 

 pits that are conspicuous on the left (lower) side 

 of the head of the witch, and its tail is much 

 larger proportionately than that of the witch. 

 It is oval in outline, about two and one-fourtb 

 times as long to the base of the caudal fin as it is 

 wide, thick-bodied, and with proportionately 

 broader caudal peduncle and tail than any of our 

 other small flatfishes. 



Its dorsal fin (60 to 76 rays) originates opposite 

 the forward edge of the eye, and is of nearly equal 

 height throughout its length. Its anal fin (45 

 to 58 rays) *° is highest about midway, and it is 

 preceded by a short, sharp spine. Its ventral 

 fins are alike on the two sides of the body, and 

 both of them are separated from the long anal 

 fin by a considerable gap. The mouth is small, 

 not gaping back to the eye, and the lips are thick 

 and fleshy like those of the yellowtail. The left 

 (under) half of each jaw is armed with one series 

 of close-set incisor-like teeth, but the right (upper) 

 side has only a few teeth, or it may even be tooth- 

 less. The scales are rough on the eyed side, 

 including the space between the eyes, but they 

 are smooth to the touch on the blind (white) side. 



Color. — The winter flounder, like other flat- 

 fishes, varies in hue according to the bottom on 

 which it lies, but it is the darkest of Gulf of Maine 

 flatfishes as a rule. Large ones are usually of 

 some shade of muddy or slightly reddish brown, 

 olive green, or dark slate above, sometimes almost 

 black. And they vary from plain or more or less 

 mottled to definitely marked with smaller or 

 larger spots of a darker shade, of the general ground 

 tone. There usually is a wide variation in this 

 respect, among any lot of flounders. And fish 

 caught on Georges Bank average more reddish in 



'» Perlmutter (Bull, Bingham Oceanogr. Coll., vol. II, Art. 2, 1947, pp. 

 19, 20) gives a detailed tabulation, and graph of the number of dorsal and 

 anal flu rays from upwards of 1,100 specimens including both the smaller 

 inshore form and the larger Georges Bank form. 





Figure 140. — Winter flounder (Pseudopleuronectes americanus) . From Goode. Drawing by H. L. Todd. 



