GEN. PTEROMYZON, PLANER'S LAMI'ERN. 341 



being generally occupied by a single pair of fish ; 

 at other times numbers of both sexes are seen to 

 frequent a general spawning-bed. It seldom much 

 exceeds a foot in length. It formerly enjoyed the 

 same reputation as P. marinus for its edible quali- 

 ties ; and it was much used, as we believe it still is, 

 as a bait for catching other fishes. Pennant says 

 that above 450,000 have been sold in a season at 

 forty -shillings per thousand, to the Dutch, who use 

 them as bait for cod ; and Mr. Yarrell informs us 

 that formerly the Thames alone supplied from one 

 million to twelve hundred thousand. Lamperns an- 

 nually. From their tenacity of life, they admit of 

 long preservation, and the Dutch use them in fish- 

 ing for turbot. 



(Sp. 150.) P. Planer L Planer's Lampern. In 

 external appearance this species resembles the last, 

 but on a close examination the differences are soon 

 observed. The fins are contiguous in P. Planer /, 

 and in the other species widely apart ; and in the 

 former the circular lip is furnished with numerous 

 papillae, forming a thickly set fringe, from which 

 structure Mr. Yarrell has named it the Fringed- 

 lipped Lampern. It was named by Bloch after his 

 friend Planer, a professor at Erfort, but Mr. Jenyns 

 is of opinion that the British fish is not the same as 

 the P. Planeri of Bloch and Blainville, although it 

 is obviously identical with the species so named by 

 Cuvier and Nilsson. In its colour and habits it does 

 not differ much from P.flutiatills. Both it and the 

 species just named are often in Scotland called nine- 



