200 
BULLETIN OF THE BUREAU OF FISHERIES 
gill rakers long, 21 or 22 on lower limb of first arch; scales moderate, ctenoid, moderately deciduous, 
extending forward on snout and on fins, the second dorsal and anal densely scaled; lateral line com- 
plete, forked at base of caudal, the branches extending on the fin; origin of spinous dorsal a little 
behind margin of opercle and about an eye’s diameter nearer origin of second dorsal than tip of 
snout; the longest spine 1.4 in head; origin of second dorsal a little in advance of anal; caudal fin 
deeply forked; anal fin similar to second dorsal, its base only a little longer; ventral fins rather small, 
inserted about an eye’s diameter nearer origin of anal than tip of lower jaw; pectoral fins rather long, 
1.15 in head, the filaments well separated from the rest of the fin, eight in number, the longest ones 
reaching nearly to origin of anal. 
Color in alcohol olivaceous; the fins dusky, the pectoral fins darkest. The fins are said to be 
mostly pale in the young. 
Only three specimens of this species — respectively, 233, 233, and 235 milimeters (9J^, 9^, and 
9 2 /s inches) in length— are at hand. This fish, although recorded from as far north as New York, 
does not appear to have been taken previously in Chesapeake Bay, where it is scarcely known by the 
fishermen. The specimens at hand were the only ones seen during extensive collecting expeditions, 
and they were trapped in a pound net in Lynnhaven Roads, Va. The species of this genus are con- 
sidered good food fishes on the Isthmus of Panama, where several species are abundant. 
Habitat . — New York to the Rio Grande. 
Chesapeake localities. — (a) Previous records: None. (6) Specimens in collection: From Lynn- 
haven Roads, Va. 
Family XL1X. — SCOMBRID/E. The mackerels 
Body fusiform, more or less compressed; head depressed above; snout pointed; caudal peduncle 
slender, with one or more keels; mouth large; premaxillary not protractile; maxillary without a 
supplemental bone; jaws with large or small sharp teeth; preopercle unarmed except in very young; 
opercle entire; gill openings large, the membranes separate, free from the isthmus; gills 4, a slit behind 
the fourth; pseudobranchite large; gill rakers long; dorsal fins 2, the first of weak spines, the second 
similar to anal, followed by detached rays, known as finlets; caudal fin large, forked. 
Scombroid fishes of the Orient have recently been studied in great detail by Kishinouve, 17 
who has grouped the fishes of that region into three families, placing (of the genera represented in 
the present report) Scomber in Scombridae and Sarda in Cybiidse. Scomberomorus, however, 
does not occur in the Orient, hence this genus is not included in Kishinouye’s work. It seems prob- 
able that a detailed study would show this genus to be as distinct and equally as much deserving 
of family rank as some of the groups recognized as families by Kishinouye. While we do not question 
the arrangement of families in Kishinouye’s very excellent work, we prefer to retain in this report 
the family Scombridae as understood by Jordan and Evermann (1896-1900 p. 863) and others, 
principally because we do not know where to place Scomberomorus in the new arrangement and we 
have neither the time nor specimens to go into a study of this matter on this occasion. 
KEY TO THE GENERA 
a. Caudal peduncle without a median lateral keel but with two small keels, one above and one below 
the median line and placed more or less on base of caudal; first dorsal with 9 to 14 feeble spines. 
b. Air bladder wanting; first dorsal with 10 to 14 weak spines Scomber, p. 201 
bb. Air bladder present; first dorsal with 9 or 10 weak spines Pneumatophorus, p. 202 
aa. Caudal peduncle with a median keel on each side and with a smaller one above and below this 
one; dorsal fin with 14 to 22 spines. 
c. Scales not forming a corselet on anterior part of body; pectorals inserted near level of the 
eyes; sides sometimes with yellowish spots and occasionally with one or more straight 
dark lines Scomberomorus, p. 203 
cc. Scales forming a corselet; pectoral fins placed low r er than eye; sides without yellow spots. 
d. Vomer toothless; sides with black longitudinal oblique bands Sarda, p. 205 
dd. Vomer with villiform teeth; sides without black longitudinal bands Thunnus, p. 207 
17 Contributions to the comparative study of the so-called scombroid fishes. Journal, College of Agriculture, Imperial Univer- 
sity, Tokyo, Vol. VIII, No. 3, (1923), pp. 293 to 475, Pis. XIII— XXXIV, fig. A-Z. Tokyo. 
