82 BULLETIN OF THE 
as do all the rows, considerably farther back of the angle of the mouth 
than it does in front of that point. The uppermost row of the four 
runs upward to near the posterior and lower quadrant of the eye, where 
it takes a trend more directly 
backward, and extends for 
a considerable distance back 
along the dorsal limit of the 
operculum. The other two 
rows are situated considerably 
nearer the lower than the up- 
Head of Lepidogobius, showing the distribution of Pe TOW, and are nearer each 
the tactile Papillew. x 1}. other than either is to the 
uppermost or the lowermost row. They also run very nearly parallel 
with each other. The lower one of these two middle rows contains the 
fewest and largest papille of the head, those of the inner mandibular 
series excepted. There are about twenty-five papilla in the lower 
row, nineteen in the next, thirty-five in the third, and fourteen in 
the fourth. 
Many of the papille of this species are distinctly excavated on their 
summits, and in such a way as to show such an arrangement as is de- 
scribed by Solger (’80, p. 375) to exist in the lower jaw of Gobius 
minutus. The excavations are in the form of grooves, or creases, which 
extend entirely across the summit of each papilla, each groove being 
somewhat broader in its middle than at the ends. In some of the rows 
these grooves are directed lengthwise of the row, while in others they 
have a direction crosswise of it. There is some variation in the 
direction of the grooves in the papille of the same row, and consider- 
ably more in some rows than in others; but the constancy in some of 
them is noticeable. In the larger papilla the grooves are much more 
pronounced than in the smaller ones, in many of these latter the exca- 
vation being a pit rather than a groove. In the lower-jaw series of this 
species, the grooves of the inner rows extend crosswise to the axis of 
the head, and those of the outer row lengthwise, thus corresponding to 
the condition found by Solger in Gobius minutus. 
In addition to the four series thus described, there are numbers of 
papille scattered on other portions of the head, particularly about the 
tip of the snout and on the opercular apparatus; in these regions 
they are particularly numerous on the suboperculum. Also on each side 
of the body, beginning immediately behind the pectoral fins, there are 
about thirteen transverse series, containing from five to ten papille 
