North American Species of Petromyzontidm. 285 



The synonymy needs little further remark. There seems to 

 be no doubt of the identity of the American P. americanus with 

 P. mar inns. It seems also certain that P. nigricans is the 

 young or river form of the same species, while A. Ucolor repre- 

 sents the larval condition, blind, with the mouth contracted and 

 toothless. 



It is also most probable that P. appendix represents a later 

 stage in the growth of the young lamprey ; but of this we are 

 not quite so certain. 



The P. lamotteni of Le Sueur has the coloration of P. ma- 

 rinas ; but the figure of the dentition is unsatisfactory and pro- 

 bably unreliable. 



Additional Note on the Lamprey of Cayuga Lake. 



BY SETH E. MEEK. 



Since the above was in the hands of the printer, I have re- 

 ceived from Mr. Seth E. Meek, now Fellow in Cornell University, 

 many specimens of the Cayuga Lake Lamprey, together with the 

 following notes, which will prove valuable for purposes of com- 

 parison. D. S. J. 



ble in length, shortest in males, 1^ to f base of first dorsal. Tail 3f in length. 

 Coloration of P. marinus, and size not much less. Abundant in Cayuga 

 Lake, New York ; not vet observed elsewhere. The differences above noted 

 are not very constant." 



This peculiar carination of the back in breeding males has not been 

 noticed by us in P. marinus. We are, however, informed by Mr. Meek, 

 that several specimens from the streams of Massachusetts, now in the Mu- 

 seum of Comparative Zoology, show the same character. 



