FISHES OP WEST COAST OF PERU. 19 



dorsal; dorsal surface of caudal peduncle black; a row of about 6 

 black spots along lateral line; a second row below lateral line; a 

 black area above base of ventrals; vertical fins dusky, darkest at tips; 

 paired fins blackish. 



Family CLUPEIDAE. 



THE HERRINGS. 



KEY TO GENERA REPRESENTED. 



a} Vertebrae about 50 in number (46 to 56) ; species of northern or southern 

 regions. 

 5\ Vomer with teeth ; ventral scutes weak, ventrals below middle of dorsal ; 

 vertebrae 50 to 56 ; skeleton rather firm. 

 &. Origin of dorsal well in advance of the middle of body. Potamalosa, p. 19. 

 &.^ Vomer without teeth ; ventral scutes very weak, the belly more or less 

 rounded; vertebrae about 52; ventrals under middle of dorsal. Skele- 

 ton weak ; flesh oily Sardinella, p. 20. 



a.* Vertebrae about 42 (40 to 44) ; tropical species with the scales large and 

 usually firmly attached ; ventrals inserted under middle of dorsal ; adipose 

 eyelid present Harengula, p. 21. 



Genus POTAMALOSA Ogilby. 



18. POTAMALOSA NOTACANTHOIDES (Steindachner). 



MACHETE. 



Clupea (Alosa) notacanthoidcs Steindachnee, Ichth. Notizen, No. 9, 1869, 



p. 20, pi. 7 ; Mazatlan. 

 Potamalosa notacanthoides Abbott, Marine Fishes of Peru, Proc. Acad. 



Nat. Sci. Phila., 1899, p. 333.— Staeks, Fishes from Ecuador and Peru, 



Proc. U. S. Nat. Mus., vol. 35, 1906, p. 778. 

 Clupea notachanthus Gtjnther, Cat. Fish. Brit. Mus., vol. 7, 1868, p. 443. — 



Delfin, Cat. Feces de Chile, 1901, p. 39. 



Five specimens, field No. 447, 12.6 to 14.3 cm. in length, and two 

 specimens, field No. 263, 22.1 and 25.5 cm. in length, all from Callao. 



Head 2.94 to 2.97 in length; depth 2.85 to 3.07; eye 4.12 to 4.85 

 in head; snout 4.85 to 5.07; maxillary 2.05 to 2.26; interorbital 4.46 

 to 4.85 ; pectoral 1.47 to 1.74 ; ventrals 2.35 to 2.76 ; dorsal scutes 23 

 to 25 ; ventral scutes 35 to 36 ; D. 20 or 21 ; A. 1-4-17. 



In these specimens there are 13 or 14 divided rays in the anal, 

 but in the smaller individuals a larger number of simple trjs is 

 discernible in front of the divided rays than in larger examples. 



Body deep, compressed, curvature of ventral outline greater than 

 that of the dorsal; head short, compressed; mouth large, oblique, 

 jaws subequal; maxillary extending slightly beyond vertical from 

 posterior border of eye ; snout short, blunt. 



Distal margin of dorsal concave, anterior raj^s longest, origin of 

 dorsal in advance of middle of body ; caudal forked nearly to base ; 



