planer's lamprey. 259 



species spawns in March and April, and is a pro- 

 lific fish. It is so tenacious of life that it will live 

 many days out of water. 



planer's lamprey. 



Petromyzon Planeri. P. pallidus, corpore annulato, oris margine 

 papilloso. 



Pale Lamprey, with annulated body, and the edges of the 



mouth papillose. 

 Petromyzon Planeri. P. corpore annulato, ore papilloso. Block. 



t.78-f.'3. 



Length from five or six to ten inches : general 

 resemblance that of the Lampern : colour olive 

 above, pale or white beneath : second dorsal fin 

 of an angular outline : tail shaped like that of the 

 Lamprey and Lampern ; mouth fiirnished with 

 small teeth : native of the rivers of Thuringia and 

 other parts of the German Empire : like most of 

 the genus, tenacious of life, living for the space of 

 a quarter of an hour when immersed in spirits of 

 wine, and moving with, violence during the whole 

 time: when thus killed in spirits, the mouth re- 

 mains open, but when the fish dies in water it is 

 shut. First observed and described by Professor 

 Planer of Erford. 



