430 BULLETIN OF THE UNITED STATES FISH COMMISSION. 
ANALYSIS OF AMERICAN AND EUROPEAN GENERA OF SCOMBRINJF. 
Finlets present (5 to 10 in number) behind soft dorsal and anal ; body 
not greatly elongate. ( Scombrince .) 
a. Caudal peduncle without median keel; dorsals well separated, the interspace 
being less than two in head; spinous dorsal short, of 9 to 12 spines ; 
body scaly ; vertebra normal ; slender teeth on vomer and palatines ; 
maxillary entirely covered by preorbital ; a fleshy lobe on each side 
of the lower jaw near its junction with the maxillary; corselet very 
small or obsolete ; gill-rakers long, slender, and numerous ; vertebra 
14 -J- 17 = 31 Scomber, 1. 
aa. Caudal peduncle with median keel ; a small keel above and one below this. 
b. Body scaleless, excepting on and about the lateral line and corselet ; dorsal 
spines 10 to 16 ; “ abdominal vertebra with their lower foramina en- 
larged*, and a portion between the vertebra proper and the hsema- 
pophyses developed in the form of a net-work or trellis.” 
c. Dorsals well separated, the interspace less than 2 in head ; corselet well de- 
veloped ; teeth small, some present on vomer, none on palatines; 
gill-rakers long, slender, and numerous; vertebra 39 Auxis, 2. 
cc. Dorsals contiguous, the interspace more than 5 in head ; palatine teeth villi- 
forrn. 
d. Vomer with teeth ; dorsal spines 11 to 13 Orcynopsis, 3. 
dd. Vomer toothless ; dorsal spines 15 to 16 ; vertebra 38 Gymnosarda, 4. 
bb . Body wholly covered with small scales, those on the corselet and lateral line 
sometimes larger ; dorsal spines 14 to 26 ; vertebra normal. 
e. Teeth of jaws slender, subconical, little, if at all, compressed; gill-rakers 
numerous ; corselet distinct. 
/. Vomer and palatiues with villiform or sand-like teeth; body robust, not 
compressed; vertebra 39 to 41.... Albacora, 5. 
ff. Vomer toothless ; palatines with a single row of rather strong, conical 
teeth ; body elongate, slightly compressed ; vertebra 50 to 54. 
Sarda, 6. 
ee. Teeth of jaws strong, subtriangular or knife-like, more or less com- 
pressed ; villiform teeth on vomer and palatines ; gill-rakers compara- 
tively few ; corselet obscure. 
g. Dorsal spines 14 to 18 ; body elongate, compressed ; head short ; snout 
short; vertebra 45 Scomberomorus, 7. 
gg. Dorsal spines 24 to 26 ; body elongate, fusiform ; snout long ; ver- 
tebra 32 -f 34 = 66 Acanthocybium, 8. 
Genus I.— SCOMBER. 
Scomber Artedi, Genera, 30, 1738. 
Scomber Linnseus, Syst. Nat., ed. x, 297, 1758 ( scombrus ). 
Pneumatophoms Jordan & Gilbert, Proc. U. S. Nat. Mus., 593, 1882 ( pneumatopborus ). 
Type: Scomber scombrus Linnaeus. 
Etymology: <7x6 p/ 3 poq, Latin, Scomber , name of the common mackerel. 
This well-known genus contains but few species, two of which are 
common in the North Atlantic, one of them being one of the most valu- 
able of food fishes. It is divisible into two subgenera, on the character 
of the air-bladder. 
