DEVELOPMENT AND LIFE HISTORY OF SOME TELEOSTS 
517 
spots are not always developed at a length of 210 mm. In structure these fish do not 
differ essentially from the 160-mm fish already described. These specimens still 
remain rather more compressed than large fish. The maxillary remains gently 
arched, and the snout sharply pointed, projecting slightly, just as in the smaller fish 
described in the foregoing section. The lateral line remains unchanged, being rather 
gently decurved under the anterior part of the soft dorsal, precisely as in adult Spanish 
mackerel. The gill rakers have increased somewhat in length, though they do not 
yet exceed a fourth the length of the pupil. Scales now are present on the soft dorsal 
and on the anal, though none can be seen on the pectorals. The dermal keel on the 
caudal peduncle is quite evident. 
A DISCUSSION OF THE RELATIONSHIP OF THE SPECIES OF SCOMBEROMORUS AND 
THE PROBABLE IDENTITY OF THE YOUNG 
The relationship of the three species of Scomberomorus known from the Atlantic 
coast of the Americas, is rather close, as indicated elsewhere. We recognize only one 
species among the young studied, though the identity of the 6.0- to 8.0-mm specimens 
described is somewhat doubtful, owing to some missing stages. 
If the very young are separable into species it would be necessary to use characters 
different from those employed in recognizing the adults. We have not discovered any 
distinguishing “juvenile” characters. The first “adult” character that develops, which 
apparently is of some value in distinguishing the kingfish, S. cavalla, from the other 
local species of the genus, is the relative position of the soft dorsal and the anal. In 
the kingfish the origin of the anal is well behind the origin of the soft dorsal, often 
nearly under the middle of the soft dorsal, whereas in the other two species the origin 
of the anal is under or more usually slightly posterior to the origin of the soft dorsal. 
The soft dorsal and anal are not well developed until the fish reach a length of about 
14 mm, and it is not until the fish reach a length of about 35 mm that the relative posi- 
tion occupied in adults is attained, as the origin of the anal is in advance of the second 
dorsal in smaller fish. The relative position of these fins remains unchanged in all the 
larger young (35 mm and upward in length) studied, the origin of the anal being slightly 
posterior to that of the second dorsal. Therefore, the specimens in our collection 
probably cannot be identified as S. cavalla. 
The next distinctive character that develops is the lateral line, which is abruptly 
decurved under the second dorsal in the kingfish, S. cavalla, and rather gradually in 
the other species. The lateral line sometimes is evident in specimens 70 mm long, but 
often not until later. Judging from the course of the lateral lines the kingfish again 
seems to be missing among the specimens that could be checked for this character. 
