3. PETROMYZONTID.E - PETROMYZON. 11 



the second, which is continuous with the caudal. Species two marine, 

 ascending rivers. (n-rpa, stone; iw^u>, to suck.) 



11. P. mai'tailis L. Great Sea Lamprey. 



Head moderate, but little longer than the "chest"; buccal disk large, 

 with numerous conical teeth, arranged in oblique series, those nearest 

 the oesophagus largest and partly bicuspid; two pairs of lunate, pecti- 

 nate lingual teeth, one in front of the other, the serrations on the an- 

 terior pair usually confluent; fins moderate, the dorsals well separated ; 

 the second dorsal with a depression on the tail ; lips moderately fringed. 

 Color olive-brown, mottled with blackish confluent patches ; dull brownish 

 below. Size much larger than any of the other species. L. 24 to 36. 

 Atlantic coasts of Europe and North America, chiefly northward, ascend- 

 ing streams in the spring to deposit its spawn. 



(Petromyzon marinus L. Syst. Nat. ; Giinther, viii, 501 ; Jordan, 348. Petromyson 

 americanus Le Sueur, Trans. Am. Pliilos. Soc. i, 363. Petromyson americanus Storer, 

 Fish Mass. 231.) 



12. P. jiigricaMS Le Sueur. Lamper-eel. 



Head very large, longer than the "chest", 6J in length ; depth about 

 13 ; body little compressed ; dorsal fins rather low, distinctly separated ; 

 eyes and mouth very large; mandibulary plate with 7 to 9 teeth; the 

 rest of the buccal disk covered with rather large teeth disposed in ob- 

 lique cross-rows, five or more in each row, some of the innermost bicus- 

 pid ; anterior as well as posterior lingual teeth pectinate ; lips fringed. 

 Coloration nearly plain ; bluish black above, pale below, usually a pale 

 spot between the eyes on the top of the head. L. 12. A rather small 

 species found along the Atlantic coasts of our Northern States, and 

 ascending streams in the spring to spawn, some individuals remaining 

 permanently in fresh water. Abundant in Cayuga Lake, N. Y., from 

 which locality the specimens were taken on which the above description 

 was based. 



(Petromyzon nigricans Le Sueur, Trans. Arner. Phil. Soc. new series, i, 385; Storer, 

 Fish Mass. 253. Ammoccetes flumatilis Jordan, 349.) 



This species is very different from the European Lampetra flumatilis. 

 It is possibly only a variety of Petromyson marinus. Numerous other 

 Lampreys have been described from our waters, but we find them un- 

 recognizable. 



