PECULIARITIES OF PLAICE FROM DIFFERENT FISHING GROUNDS. 333 



Pacific form of the plaice exists. The flat-fishes of California and the 

 west coast of America generally have been attentively studied by 

 American zoologists, and are captured regularly for the market; but 

 no specimens of this form have been noticed except the above, nor have 

 any been discovered in Japan. The plaice-like form again is not known 

 at present to extend further north than Herendeen Bay. Flat-fish have 

 been collected at more northern places on the west coast of Alaska, but 

 specimens of this form were not among them. It appears, therefore, 

 that the species in the Pacific does not extend so far north or so far 

 southwards as in the Atlantic ; but, on the other hand, it is found on 

 the west shores as well as on the east, whereas on the west side of the 

 Atlantic it is absent. 



Pleuronedes glacialis. Now to the northward, where the plaice 

 disappears, the northern species, glacialis, is found in its stead, and this 

 species occurs along all the northern coasts of Europe and America, 

 and on the east coast of America. It presents local variations, and has 

 been described under various names, but there is no doubt that it 

 constitutes a single species, which in many respects is closely allied to 

 the plaice. The following are the principal synonyms and references : — 



Pleuronedes glacialis, Pallas, Zoogr. Rosso-Asiatica, iii. p. 424. 



Pleuronedes cicatricosus, Pallas, ibid. 



PI. glacialis, Richardson, Voy. H.M.S. Herald, p. 166 (1852). Bean, 

 Proc. U.S. Nat. ]\Ius. 1881, p. 241 (Kotzebue Sound, Northern Alaska). 

 Jordan and Gilbert, Synopsis Fish. N.A. Smitt, Scandinavian Fishes, 

 1893. 



Platessa chinensis, Lilljeborg, Svensk Vet. Akad. Hand], 1850. 



Platessa glabra, Storer, Proc. Boston Soc. Nat. Hist. 1843, p. 130. 



Liopsetta glabra, Gill, Proc. Acad. Nat. Sci. Philad. 1864. 



Euchalarodus Puinami, Gill, Proc. Acad. Nat. Sci. Phil. 1864, p. 216. 



Pleuronedes glaher, Goode and Bean, Proc. U.S. Nat. INIus. 1878, p. 

 347. Bean, ibid, p. 345. 



Pleuronedes Franklinii, Giinther, Cat. Fish. Brit. Mus. iv. 1802, 

 p. 442. 



Pallas first described P. glacialis in 1773, in his account of his 

 journeys through various provinces of Russia; and in his larger work, 

 published in 1811, repeated the description with but little modification. 

 His specimens were taken in the Kara Sea and at the mouth of the river 

 Obi. The chief characters given are the absence of spiny tubercles like 

 those of the flounder; the ridge behind the eyes rough, but not divided 

 into tubercles ; the middle rays of the fins on the coloured side 

 roughened with very minute spines ; dorsal rays, 56; anal, 39. The upper 

 side is also squamulis asperis gramdaUim, which probably means that 

 the upper side was spinulated all over. 



