118 CALIFORNIA FISH AND GAME. 
THE MACKEREL AND MACKEREL-LIKE FISHES OF 
CALIFORNIA.* 
By EDWIN CHAPIN STARKS, Stanford University. 
The group composing the mackerel and mackerel-like fishes is com- 
mercially one of the world’s most important groups of fishes containing 
as it does the true mackerel of the Atlantic coast and the albacore of 
the California coast. Only the herring group surpasses it in value. 
It contains some of the swiftest fishes that swim as well as some of the 
largest. Mest members of the group are built for speed, the fins fold- 
ing into grooves in the body, the mouth and gill covers fitting tightly 
and smoothly, and with no projections on the head or body to break 
the continuous curves. The contours are said by nautical engineers 
to be perfect for passage through the water with the least resistance. 
But among these fishes are many variations of form of body, some of 
which are not at all adapted to swift swimming. 
Usually the head is sharp, the tail slender and with a widely forked 
caudal fin, the scales very small and thin, and the color silvery and 
metallic. Usually the dorsal and anal are elevated to a point in front 
with the outline just behind the point concave. Many of them have the 
pectoral fins seythe-shaped, and most of them have a keel on each side 
of the tail. 
These fishes are closely related to the bass-like fishes. Though 
differing from them very much in the extremes they grade into them, 
on the other hand, so that they can be separated only arbitrarily. 
- Among the mackerel-like fishes are several pelagic fishes or fishes of 
the high seas, that are occasionally taken on our shores, but so rarely 
that there is little reason for including them in a report of this 
character. 
GLOSSARY. 
Air bladder: A thin walled sae lying in the upper part of the 
abdominal cavity. 
Anal fin: The fin on the lower side of the body. Sometimes in two 
parts but never paired (two side by side). 
Caudal fin: The tail fin. 
Compressed: Said of the body when it is flattened from side to side. 
Dorsal fin: The fin on the back, often divided into two fins, the first 
usually of stiff spines and hence called spinous dorsal. 
Finlets: The little detached fins behind the dorsal and anal in the 
mackerels. 
Keel: The sharp projecting ridge at the side of the tail. 
Maxillary: The flattened bone bordering the mouth above. 
Pectoral fin: The uppermost of the paired fins. Situated close to 
the gill opening. 
Ventral fins: The paired fins on the lower part of the breast, close 
under the pectorals in these fishes. 
*A report of the Committee on Zoological Investigations of the State Council of 
Defense. 
