North American Species of Petromyzontidce. 283 



form. The Ammoccetesborealis of Agassi/ is probably the larval 

 form of this species, as the long description agrees almost entirely 

 with a certain stage in the larva of P. marinus, and it is pre- 

 sumable that P. coitcolor passes through similar stages of growth. 

 P. concolor is certainly known to occur in the Upper Great 

 Lakes, whither the other species have not been traced. 



The Ammocoetes cepypterus of Abbott, likewise based on a lar- 

 val example, is not described in such a way as to enable us posi- 

 tively to identify it. Of the two species (concolor, branchialis) 

 thus far found in the Ohio Basin, the description most resembles 

 the former. 



4.-PETROMYZON MARINUS. 



Petromyzon maculosus Artedi, Ichtbyol., 90, 1738 (non-binomial.) European 



seas. 

 Petromyzon marinus Linnaeus, Syst. Nat., X, 1785, 230 (after Artedi, etc.). 



AMERICAN SYNONYMY. 



o. Anadromous f orm (marinus). 



Petromyzon marinus Giinther, Cat. Fish. Brit. Mus., 1870, VIII, 501 (Nova 

 Scotia ; Merrimack R. ; New York.). Jordan & Gilbert, Synopsis 

 Fish. N. A., 1883, 11. Bean, Proc. U. S. Nat, Mus., 1883, 367 (Ha- 

 vre de Grace \ Jordan Cat, Fish. N. A., 1885, 4 ; and of recent 

 writers generally. 



Petromyzon Americanus Le Sueur, Trans. Am. Phil. Soc, 1818, 373 (marine 

 form). Storer, Rept. Fish. Mass., 1839, 195 (Charlestown). De Kay, 

 New York Fauna, Fish, 1842, 379, pi. 66. f. 216. Gray, Cat. Chondr.. 

 Fish., 1851, 139. Storer, Synopsis, 1846, 256; Storer, Hist. Fish. 

 Mass.. 1867, 251, pi. 38, f. 4 (Massachusetts). 



Petromyzon nigricans Le Sueur, Trans. Am. Phil. Soc, 1818, 385 (half grown). 

 Storer, Rept. Fish. Mass., 1839, 197. De Kay, New York Fauna, 

 Fishes, 1842, 381, pi. 79, f. 247 (copied). Linsley, "Am. Journ. Sci. 

 Arts., 1844," (Connecticut). Storer, Synopsis, 1846, 517. Gray, Cat, 

 Chondr. Fish., 1851, 139. Storer, Hist, Fish. Mass., 1867, 253, pi. 

 39, f. 6. 



Ammocoetes bicolor Le Sueur, Trans. Am. Phil. Soc, 1818, 386 (larval form). 

 Storer, Rept, Fish. Mass., 1839, 198 (copied). DeKay, New York 

 Fauna, Fishes, 1842, 383, pi. 79, f . 248 (Connecticut R. ). Gray, Cat. 

 Chondr. Fish., 1851. 146 (name preoccupied). 



Petromyzon appendix DeKay, New York Fauna, Fishes, 1842, 381, pi. 68, 

 f. 211 (Providence ; Hudson River ; young, in fresh water). Gray, 

 Cat. Chondr. Fish., 1851, 148. 



Ammocoeies appendix Jordan & Gilbert, Synopsis Fish. N. A., 1883, 868 

 (copied). 



