195 
case in the other specimens of this species. The specimens belonging to this latter form were 
found at Station 164. They are characterised also by the shape of the tergum, the scutal margin 
of which is not straight, but somewhat convex, which makes this valve much broader than in 
the ordinary form of the species (Pl. XVIII, fig. 2a and 4). I intended at first to describe this 
form as a variety of this species; since I found afterwards, however, that some specimens from 
the same locality show these differences in a smaller degree, and others not at all, I prefer 
to point out the variability without proposing a special name for the form that seems to 
show this particularity in the highest degree. 
There remains no doubt in my mind that this form really corresponds with the species I 
described in the Report on the Cirripedia of the Challenger as B. socéal’s. As regards the 
important difference between the definition given in the report of 1883, and the description 
given here, namely that I ranged the species there under those that have the parietes permeated, 
I now find that such pores are absent. I have already explained on p. 192, how this error 
may have arisen. 
Further, at another Station, a few very small specifhens of a Balanus were collected which 
I suppose to belong also to this species. Their opercular valves are wanting; the diameter 
near the basis of the largest specimen of the sample measures at the most 3 mm.; the shells are 
white, have large orifices; their alae and radii show the same shape as in &. soczalis. They 
were found attached to small Gastropodous-shells (Scadarza?), which were collected at: 
Stat. 205. Lohio-bay, Buton-strait. Depth 22 m. Bottom: sandy mud. 
11. Balanus maldivensis Borradaile. Pl. XVIII, fig. 13—109. 
BORRADAILE, L. A., Marine Crustaceans. Parts IV—VII in “The Fauna and Geography of 
the Maldive and Laccadive Archipelagoes”’. Vol. I. Part 4. 1903. p. 442, fig. 118: 
This species, which according to BorrapaiLe, occurs in S. Nilandu Atoll (Maldive or 
Laccadive Archipelagoes) seems to be a rather common species in the Malay Archipelago. 
BorrapalLe’s description in the main is exact — a somewhat more extensive one, however, will 
not be judged superfluous. 
It is a species (PI. XVIII, fig. 13) with thick solid walls of a conical or steeply-conical 
shape; it is often somewhat compressed laterally; the surface of the parietes looks gnarled and 
often ringed, but not regularly ribbed. The radii are elongately-triangular, having the summits 
broad and nearly horizontal, and terminating downwards in a point. The summits of the radii 
are, moreover, straight or slightly concave, the alae, in the latter case, extending slightly beyond 
the radii. The outer surface of the radii is indistinctly striped horizontally, and lies somewhat 
deeper than that of the compartments, which gives a very typical appearance to the shell. 
Orifice oval when seen from above, with the carinal extremity pointed, and the rostral rounded 
or rhomboidal. Parietes and radii without pores, the inner side of the parietes strengthened by 
longitudinal ribs. Basis also without regular canals; at the circumference, however, shallow pores 
are seen beginning in the intervals between the bases of the ribs placed against the parietes. 
.It is a small species: the diameter of the larger specimens measures from 6—7 mm. near the 
basis, their height from 4—5'/, mm. 
67 
