558 
BULLETIN OF THE BUREAU OF FISHERIES 
size, becoming proportionately shorter later in life) reaches nearly to or even past the 
vent in some specimens, also is evident. The interorbital space, too, is narrower, 
being equal to only about half the width of the pupil, whereas in bosci it is fully equal 
to the width of the pupil. Furthermore, ginsburgi has two scales on the base of the 
caudal fin which the other species does not possess. Pigmentation in ginsburgi in the 
specimens at hand has not progressed as far as in bosci of the same size. However, a 
considerable degree of variation in color development appears to exist among both 
species and the degree of pigmentation may be of no specific importance (fig. 49). 
General characteristics of the young. — In general young Gobiosoma, even before 
fin rays are developed, may be recognized by the rather deep body, by the vertical 
mouth, by the air bladder which is visible as a clear area through the body wall, and, 
perhaps most important of all, by the pigment spots present, which remain about the 
same throughout the larval stages, or until pigmentation becomes general. These 
spots are black and consist of a single row occupying the median ventral line of the 
body. Two elongate spots (short lines) are situated under the head and chest, one or 
two immediately in advance of the vent and several behind the vent, or along the base 
Figure 49 . — Oobiosoma ginsburgi. From a specimen 15 mm long. 
of the anal when that member becomes developed, the last spot of the series being at 
the base of the caudal when that fin becomes differentiated. When the dorsal and 
anal fins become developed, at a length of about 5.0 mm, the rather low number (gen- 
erally 11 to 13) of rays in each fin is of much help in identification. At about this size 
the body becomes quite robust, the head rather broad, the caudal peduncle is short 
and deep, and the mouth is less nearly vertical than previously. Identification now 
is much simplified. 
DISTRIBUTION OF THE YOUNG 
Young Gobiosoma were taken in tow nets and seines in many places and over a 
wide variety of conditions, ranging from brackish water creeks and ponds, through 
salt and brackish estuaries, in Beaufort Harbor, along Bogue and Shackleford Banks 
(both shores) and at sea as far as approximately 15 miles offshore in 10 to 12 fathoms 
of water. The great majority of the hundreds of specimens collected were taken on 
the bottom, although occasionally a few appeared in the surface tow. The indica- 
tions are, then, that the young, like the adults, dwell principally on the bottom. 
Since the larvae (under about 10 mm in length) could not be separated as to species, 
the distribution cannot be given separately for each species. Among the young fish 
that are recognizable, bosci was taken only in shallow water and only once at an 
outside station, that is, about 1 mile off Bogue Banks in a few fathoms of water. 
G. ginsburgi, on the other hand, was taken in both shallow and rather deep water 
and frequently at offshore stations. 
