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angle and is of considerable breadth. The basal margin is slightly hollowed out, and no crests 
for the depressor muscles could be seen. 
The structure of the animal's body shows the following peculiarities: 
Mouth. Labrum (Pl. XX, fig. 11) with the notch wide at entrance and not very 
deep. The outer edge of the lateral parts rounded. Two teeth on each side of notch, short 
delicate hairs disposed along the edge. The whole shape of the thickened portion of the labrum 
more rhombiform than triangular. 
Palpi elongate with distal extremity slightly turned up, hence the superior margin is 
somewhat hollowed out. Hairs numerous and delicate: a dense row of shorter ones along 
superior margin, and a great number of longer hairs scattered irregularly over outer surface. 
Mandible (Pl. XX, fig. 12) with three well-developed teeth, and teeth 4 and 5 and 
inferior angle blunt and almost rudimentary. Distance between extremities of teeth 1 and 
2 slightly longer than that between 2 and 3. Half way between the latter two teeth in both 
mandibulae a small additional tooth is observed. The inferior angle, which in the mandible of 
the one side ends bluntly, terminates into a short spine in the other. 
Maxilla (Pl. XX, fig. 13 and 13*) has the free edge straight, a small notch under 
upper pair of spines, and 5 spines on the middle portion of the edge between the notch and 
the slightly longer inferior pair. Differences in length of the spines not very considerable. 
Outer maxilla (Pl. XX, fig. 14) with the outer lobe of oval shape, the inner and 
outer margins rounded equally strongly. On the outer half of the inner surface this lobe is 
covered with numerous delicate hairs; while the other species have a single or double row ot 
hairs, extending from the outer to the inner lobe, quite a broad group of numerous hairs is seen 
in this species. Inner lobe rounded, with longer hairs disposed as usual along inner margin. 
Cirri. First pair has the two rami very unequal of 8 and 20 segments respectively. 
The segments of the shorter ramus very protuberant on the anterior face. 
Second pair bas the rami slightly unequal of 10 (11) and 12 segments. The segments 
are rounded, not protuberant, on their anterior faces. Hairs on different segments numerous, 
they do not form, however, such dense tufts as on the same cirrus of most other species of 
Balanus. On all the segments, of the outer as well as of the inner ramus, with the exception 
of the last segment, on the distal half of the exterior face, rows of small spine-like teeth are 
seen. These are of a peculiar form, and look like rounded scales bearing one, two, or three 
sharp spines on their margins. 
Third pair has unequal rami of 12 and 15 segments. Similar, but slightly stronger 
rounded scales with small teeth on the margin, as on the second cirrus, form several transverse 
rows on the distal half and outer surface of the 8 to 9 lower segments of both rami. Anterior 
margin developed into a rounded protuberance. 
The fourth pair has the rami slightly unequal, of 19 and 21 segments. Triangular 
spine-like teeth (Pl. XX, fig. 15 and 15%), stronger than the corresponding ones on the 2™4 
and 3" cirri, form transverse comb-like rows and are disposed on both segments of the pedicel, 
near the extremity, and on about 10 of the lower segments of the outer ramus of this cirrus. 
They are also seen on the other ramus, but there they are much less strong. 
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