122 BRITISH FRESHWATER FISHES 



specific name clupeoides given to it by the French 

 naturalist Lacepede in 1803. 



In form and coloration the Powan is very similar 

 to the Pollan of Lough Neagh, from which it differs 

 especially in having the mouth smaller and sub- 

 terminal or inferior, with the maxillary just reaching 

 the vertical from the anterior edge of the eye, and 

 with the lower jaw included within the upper. The 

 snout is vertically or somewhat obliquely truncated, 

 and the fins are larger than in the Pollan, the 

 longest dorsal ray measuring from four-fifths to 

 seven-eighths of the length of the head, and the 

 pectoral extending more than one-half of the distance 

 from its base to the pelvics. 



The usual length of the Powan in Loch Lomond 

 is about a foot, but it grows to 1 8 inches or more, 

 sometimes attaining a weight of 2 Ibs. ; in Loch 

 Eck it is smaller, and three examples from that 

 locality sent to me by Professor D'Arcy Thompson 

 are only 8 or 9 inches long ; one of these is figured 

 (PI. XVII, Fig. i). 



Parnell's account of this species, written in 1838, 

 is as follows : " These fish are found in Loch 

 Lomond in great numbers, where they are named 

 Powan or Freshwater Herring. They are caught 

 from the month of March until September with large 

 drag-nets, and occasional instances have occurred 

 in which a few have been taken with a small 

 artificial fly ; a minnow or bait they have never 

 been known to touch. Early in the morning and 

 late in the evening large shoals of them are observed 

 approaching the shores in search of food, and rippling 

 the surface of the water with their fins as they 

 proceed. In this respect they resemble in their 



