No. VI 



NOTICES OF THE FISHES. 



BY 



JOHN RICHARDSON, M.D., 



SURGEON TO THE EXPEDITION. 



re much 



some of the fish, observed by the Expedition, than may at first sight appear to be 

 necessary ; because I wished to put Ichthyologists in possession of as many facts as I 

 could, respecting species which may not soon come under the notice of another 

 observer. I was also desirous of enabling those who are versant in this branch of 

 Natural History, to decide whether they may, or may not, have been already described 

 by other authors ; a point on which my own opinion is of little value. The descriptions 

 were, except in one or two instances, which are noted, taken upon the spot, from 

 recent specimens. The disadvantages under which we frequently laboured in doing 

 this, will be apparent to those who have read the Narrative of the Journey ; and 

 will, I hope, be esteemed a sufficient excuse for diffuseness on the one hand, and 



omissions on the other. 



Petromyzon Fluvialis, L. Lesser Lamprey. 



A lamprey, bearing an exact resemblance in size and appearance to the one 

 figured by Bloch, t. ccccxv. f. 2., under the name of P. argenteus (and which 

 Cuvier, Reg. An. torn, ii, p. 118, considers to be the same with P. fluvialis,) 

 was found in Great Slave Lake, adhering to an inconnu, (salmo Mackenzii). It 

 had the large eyes, and, comparatively, large mouth, represented in Bloch's figure, 

 with the teeth of the P. fluvialis. The size of its eyes would seem to mark it as a 



young fish. 



Accipenser Ruthenus. Sterlet. 



Cuvier Keg. An. ii. p. 142. Gmel. Lin. Syst. Nat. p. 1485. Block, t. 89. 



Pennant's Arctic Zoohgy, ii. p. 358. 

 Accipensere Strelet, Lacepede, torn 



caught in great 



the Saskatchawan, but is not known to exist in the more northerly rivers, that 



4 X 



