20Ó 



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 (PI. 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. 



Pal pi 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 (PI. 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 (PI. XX, fig. 13 and 13*) lias 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 (PI. 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 doublé 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 has 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 (PI. XX, fig. 15 and 15*), stronger than the corresponding ones on the 2 nJ 

 and 3 ld 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. 

 The)- are also seen on the other ramus, but there they are much less strong. 



78 



