40 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 



3. The Frigate Mackerel. Auxis thazard. Plate V. 



III. SPECIES OF LARGE SIZE.— The dorsal fins are not well 

 separated; well-developed keel at the sides of the root of the tail; 

 the body is wholly covered with small scales. There are four species 

 in this group, which may further be subdivided into two divisions : 



a. Large species in which a well defined corslet is present : 



4. The Horse Mackerel. Thunnus thynus. Plate VI. . 



The mouth is wide; on the jaws is a series of cone-like teeth; on 

 the roof of the mouth are bands of sand-like teeth; about 14 spines 

 on the first dorsal fin; the eye is small; the body is very stout and 

 thick, and reaches a very great size; its color is dark blue above, and 

 grayish below with silvery spots. 



5. The Bonito. Sarda sarda. Plate VII. 



Body elongate; the corslet is small but distinct. The mouth is 

 large; strong, cone-shaped tegth are on the jaws and the roof of the 

 mouth; the first dorsal fin is long, with about 20 strong spines; the 

 second is small, followed by 8 or 9 finlets; no air bladder; dark steel 

 blue above, with numerous narrow, dark stripes from the back 

 obliquely downward and forward; silvery below. 



b. Large species in which a well defined corslet is not present : 



6. The Spanish Mackerel. Scombcromorusmaculatus. Plate VIII. 



Head pointed, short and small; mouth wide, with strong knife- 

 like teeth on the jaws; fine sand-like teeth on the roof of the mouth; 

 air bladder present; first dorsal fin with about 17 spines; color 

 silvery, bluish above; sides with many ellipitcal spots of yellowish 

 bronze color; fins variously colored, white, blackish, and yellowish. 



7. The Kingfish. Scomberomorus regalis. Plate IX. 



Similar in all respects to the Spanish Mackerel, except that its 

 sides have two blackish, longitudinal bands which cross the lateral 



