Storer’s Synopsis of the Fishes of North America. 523 
strie. The lateral projections of the snout are prominent, and margined with very strong 
crenulations, which are longer than in either of the species contained in Cuvier’s “ Histoire 
Naturelle des Poissons.” Two distinct spines at the anterior superior angle of the eye. 
Opercular spine of moderate size, not elevated at its base above the opercular plate. Pre- 
opercular spine large, naked at its posterior extremity, raised and crenulated along its whole 
outer edge. Length of the head equal to one fourth the length of the body. Length of the 
pectoral fins equal to nearly one third the length of the head. The caudal fin is quite deeply 
emarginated ; the outermost rays projecting. 
IDLING TTBE Yea, UN TI ORS Length, 12 inches. 
Massachusetts Bay, Srorrr. 
Prionotus pilatus, Storer, Proceed. Bost. Soc. Nat. Hist., 1 p. 77. 
GENUS ARGYREIOSUS, Lacep. 
3. Argyreiosus unimaculatus, BarcueLper. 
Body nearly circular, much compressed, being less than one tenth of an inch in thickness. 
Breadth, one and one tenth inches. Profile nearly vertical. Lower jaw the longer, and 
hooked. Eyes one tenth of an inch in diameter. A filament, half an inch in length, 
arises on the back in a vertical plane with the origin of the pectoral fin; three tenths of an 
inch back of this are three very minute spines. Several finlets upon the back and abdomen. 
Pectoral fins three-tenths of an inch long ; caudal fin deeply forked. 
Preserved in spirit, above the lateral line the color is dark; below it, silvery. Upon the 
Jateral line, which passes in nearly a right line from the superior angle of the gill-covers to 
the base of the caudal rays, is a nearly circular black spot, the anterior edge of which is just 
touched by the pectoral fin when depressed. 
D. (?). P.16. V.(2). A. (?). C.14. Length, 13, inches to the base of the caudal fin. 
Maine, BarcureLper. 
Argyreiosus unimaculatus, BATcHELDER, Proceed. Bost. Soc. Nat. Hist.; u. p. 78. 
GENUS LEPTOCEPHALUS, Pennant. 
Have the cleft of the gills open in front of the pectorals, and the body 
compressed like a riband. Their head is extremely small, with a short and 
rather pointed muzzle, the pectorals almost imperceptible or actually wanting ; 
the dorsal and anal in like manner scarcely visible, united together at the point 
of the tail; the intestines occupy only an extremely narrow line along the in- 
ferior edge. 
