328 PECULIAltlTIES OF PLAICE FROM DIFFERENT FISHING GROUNDS. 



and liere Duncker does not give details, but simply states that the anal 

 rays are mostly 51 to 55, the dorsal 66 to 80, aud the gill-rakers mostly 

 10 or 11. 



In describing some specimens from the Baltic in this Journal* Mr. 

 Holt referred to two spinulated specimens of the plaice, one from the 

 south coast of Iceland, and one from the Great Fisher Bank in the 

 North Sea. These specimens were among the collections left by Mr. 

 Holt at Cleethorpes which came under my charge. I have examined 

 them, and recorded their characters in the tabular lists appended to this 

 paper. They are both males of large size, and except in the greater 

 size of the Iceland specimen do not differ much from the largest of 

 the males I have examined from beyond the Dogger Bank. In both 

 specimen'', as often occurs in the higher degrees of spinulation, this 

 character is developed slightly on the head and body on the lower 

 side. It never occurs on the fin-rays of the lower side, because there 

 the scales are virtually obsolete. In the Iceland specimen the scales 

 are spinulated all over the upper side of the body except below the 

 pectoral fin, and also very slightly on the head and interspinous regions 

 on the lower side. In the Fisher Bank specimen the spinulation 

 extends all over both sides, also with the same exception, but is much 

 weaker on the lower side than on the upper. 



We have next to consider the plaice of the IJaltic, samples of which 

 are described by Duncker. Some of the specimens mentioned by Holt 

 in the paper above cited came into my hands, and their characters are 

 detailed in the tabular lists. The plaice of the Cattegat occupy 

 geographically a somewhat intermediate position, and we may examine 

 their characteristics before referring to the fish of the Baltic proper. 

 Duncker remarks of the Cattegat plaice that they resemble those of 

 Heligoland in all other respects, but differ in their enormous height 

 of body and the shortness of the head. This is exactly what might 

 be expected when we know that Duncker's sample from Heligoland 

 consisted chiefly of very young and small specimens of a large-sized 

 race. The males of Duncker's Cattegat sample were from 29"5 to 

 39-4 cm. in total length, and 10 in number; of females there were 30 

 specimens 28*0 to 38"G cm. in length. They were thus nearly all larger 

 than the largest of the Heligoland specimens. Four of the 10 males 

 had no spinulation, two had degree 2, and the rest degree 1. One of 

 the specimens without spinulation was 39'4 cm. long, one 35"0 cm., one 

 341 cm., and one 29*5 cm. According to Petersen's recordst some 

 male plaice are immature in the Cattegat at 32"o cm., if not even at a 

 larger size. But in none of my samples is a male specimen so large 

 as 394 cm. entirely without spinulation. I find it difficult to believe 

 * Vol. iii. p. 198. + Report of the Danish Biological Station, iv. , for 1893. 



