516 
BULLETIN OP THE BUREAU OF FISHERIES 
Specimens 85 to Jfi mm long. — Six specimens of about this size are at hand. The 
advancement over the 25-mm fish is not great. The upper jaw projects less promi- 
nently, and the articulation of the premaxillaries no longer is marked by a definite 
groove. The preopercular spines have been almost completely absorbed. In some 
specimens of this size a slight indication of a lateral line is present. The second dorsal 
and anal now have attained more nearly the relative position occupied in adult fish, 
as the origins are about opposite each other. (In adult S. maculatus and S. regalis 
the origin of the anal generally is slightly behind that of the second dorsal, whereas 
in S', cavalla it often is nearly under the middle of the second dorsal). The rays of 
these fins now are quite fully developed. The following counts are based on one 
specimen: D. XIX-17-VII; A. II, 17- VIII; vertebrae 22+31=53. 
Pigmentation remains about as in the 25-mm fish, except that black points on 
the middle of the side have become more numerous and more concentrated and tend 
to form a lateral band posteriorly. Much variation in the amount of black pigment 
on the spinous dorsal occurs among specimens. Generally the anterior part of the 
fin, to the fourth or fifth spine, is mostly black. 
Specimens 60 to 70 mm long. — The body remains quite strongly compressed. It 
does not differ in proportionate depth from the smaller fish described in the preceding 
section. The head is proportionately much shorter, however, being contained about 
3.3 times in the standard length. The snout projects less prominently, the anterior 
pair of enlarged teeth no longer being far in advance of the mandible. The maxillary 
remains slightly arched, but much less so than in smaller specimens, having become 
gradually less bent since a length of about 14 mm was attained, reaching below 
posterior margin of pupil, and being contained about 1.7 times in the head. The 
lateral line is fairly well defined. It is curved downward rather gradually under the 
anterior rays of the soft dorsal, and posteriorly it is undulating. Gill rakers are very 
short, mere points, eight or nine can be seen. Vertebrae 23+30=53 in one specimen 
counted. 
The body is mostly silvery; more or less brownish on the back. The anterior 
part of the spinous dorsal, involving 3 to 5 spines, is wholly black, the rest of the fin 
has only a black margin, precisely as in adult Spanish mackerel. 
Specimens 85 to 100 mm long. — Fish of this size and for sometime afterwards 
remain more strongly compressed than adults. The upper jaw projects little at this 
size, the teeth remain strong, but less so than in younger fish; and the caudal fin is now 
broadly forked, about as in the adult. No dermal keel is as yet evident in the lateral 
line on the caudal peduncle. The following counts and proportions are based on a 
specimen 97 mm long: Head 3.8; depth 4.6 in standard length; snout 2.8, maxillary 
1.8 in head; D. XVII-16-VIII; A. II, 14-IX; gill rakers minute, 9; vertebrae 
22+31 = 53. 
The color is bright silvery, rather bluish silvery above. No spots or lines are dis- 
cernible in the preserved specimens at hand (fig. 10). 
Specimen 160 mm long. — A single fish of this length (and none intermediate of 
this one and one 115 mm long) is at hand. The 160-mm fish does not differ greatly 
from the smaller group described in the preceding section. The proportions given for 
the smaller fish have not changed. 
No change in color appears to have taken place. No indications of spots or 
other markings are present on the body in the old preserved specimen studied. 
Specimens 210 to 225 mm long. — One specimen of each length given is at hand. 
These fish were recently preserved. The larger one has dark spots (yellow in life) 
on the sides as in the adults. The smaller one has none, which seems to show that the 
