240 
1. MorpaciA MORDAX. AUSTRALIAN LAMPERN. 
Petromyzon mordaz, Rich. Voy. Erebus & Terror, t. 38, 1845.— 
Mordacia mordax, Gray, Proc. Zool. Soc. 1851. 
Hab. Tasmania. 
Species of Doubtful Situation in the Family. 
1. PeTROMYZON APPENDIX. SMALL LAMPREY. 
Petromyzon appendix, De Kay, Nat. Hist. of New York, 381. pl. 64. 
f. 211. pt. 1; Zool. 1842. 
Hab. N. America, Hudson River. 
**A ring of irregular-shaped corneous processes within the oral 
orifice, and a large isolated double tooth of the same texture on the 
inferior portion of the mouth.” —De Kay. 
2. PETROMYZON TRIDENTATUS. TRIDENTATE LAMPREY. 
Petromyzon tridentatus, Gairdener, Rich. Faun. Bor. Amer. 293, 
1836; De Kay, Nat. Hist. of New York, 381. pt. 1; Zool. 1842. 
Hab. N. America, Falls of the Walamet. 
3. PETROMYZON ARGENTEUS. SiLveRY LAMPREY. 
Petromyzon argenteus, Bloch, t. 415. f. 2; Schneid. Bloch, 532. 
t. 102. f. 1, 1801; Shaw, Gen. Zool. v. pt. 2. p. 262, 1841. 
Hab. Indian Seas. 
4, PeTRoMYZON BICOLOR. BriLLiAntT LAMPREY. 
Petromyzon bicolor, Shaw, Gen. Zool. v. pt. 2. p. 263, 1804.— 
Petromyzon niger, Lacépéde, iv. 667. 
Hab. Europe, Seine. 
5. PrTRoMYZON PLUMBEUS. LEADEN LAMPREY. 
Petromyzon plumbeus, Shaw, Gen. Zool. v. pt. 2. p. 263, 1804. 
—Petromyzon Septeil, Lacépéde, iv. 667. 
Hab. Europe, Seine. 
Bs. Ammoceetina. Teeth none; eyes none. 
7. AMMOCETES. 
Teeth none. 
Ammocetes, Dum. Zool. Anal.; Cuv. Rég. An. ii. 118, 1817; 
Mill. Abhandl. Akad. Berlin, 1834, 8 (1836). —1Lampreda, Rafin. 
Anal. Nat. 94, 1815. 
1. AMMOC@TES BRANCHIALIS. Pripsr or SANDPIPER. 
Ammocetes branchialis, Dum. ; Flem. Brit. An. 164. sp. 3, 1828; 
Cuy. Rég. An. 406, 1829; Mill. Mém. de l’Acad. Berlin, 1834 ; 
Jen. Man. Brit. Vert. 522. sp. 212, 1835; Yarr. Brit. Fish. 2 ed. ii. 
