COMPARATIVE STUDY OF SCOMBROID FISHES. 
403 
fishes—narrow premaxillary which is not protractile and wants a dorsal process, 
and a small supplementary bone attached to the posterior end of the premaxillary. 
This family has remote relations to the Cybiidae. The genus Grammatorcynus 
of the Cybiidae has the same number of vertebrae as the mackerels, and pyloric 
coeca are also more or less alike. 
Starks (69) rightly remarks that “ if we could eliminate the genus Scom¬ 
ber, the family (Scombridae in wide sense) would be much more compact, as 
it stands farther from the other genera than they do from each other.” 
Mackerels are rather small, grow to a length of about 40 cm. and a weight 
of about one kg. They swim generally in the middle or lower layers of the 
coastal water, and enter into bays and inlets, in shoals. Widely distributed in 
temperate and subtropical regions. 
Key to the genera of the Scombridae. 
Body elongated and fusiform, vomer and palatines toothed. Scomber. 
Body deep and compressed, vomer and palatines toothless, gill-rakers very 
long, visible from the gape of the mouth, interspinous bones of the second 
dorsal and the anal are flattened. Rastr eiliger. 
Genus Scomber. 
Scomber, Linnaeus (s. str.) 1758 ; Cuvier, 1817. 
Teeth minute, in both jaws in one row, on the vomer in paired oblique 
patches and on palatines in one row. 
Only two good species are known, and only one species is found in the 
Pacific Ocean. 
Scomber japonic us Houttouyn. 
Saba. 
Figs. 1, 7, 16, 28-30. 
Scomber japonicus Houttouyn, Mémoires de Harlem, XX, 331, 1782; Lacépède, Hist* 
Nat. Poiss. HI, 45, 1802 ; Cuv. & Val. Hist. Nat. Poiss. VIII, 54, 1831 ; Kishinouye, 
Sui. Gak. Ho, I, 4, PL I, Fig. 1, 1915. 
Scomber pneumatophnrus Schlegel, Fauna Japon., Poiss. 94, Tab. 47, Figs. 1, 2, 1850. 
Scomber saba Bleeker, Verb. Bat. Gen. XXVI, 95, 1S57. 
Scomber janesaba Bleeker, Verb. Bat. Gen. XXVI, 96, 1857. 
? Scomber tapeinocephalus Bleeker, Verb. Bat. Gen. XXVI, 97, Tab. 7, lig. 2, 1857. 
Scomber colias Kishinouye, Joarn. Fish. Bureau, II, 1, Pis. I, II, 1893. 
D. 9-12, 12, 5. A. 1, 12-13, 5. Vert. 14 + 17. Gill-rakers 13 + 23. 
Body fusiform and compressed, its height nearly equal to the length of the 
head. Teeth minute, about 60 in each jaw. The scales in the dorsal hah of 
