228 
Cirri. Cirrus of second pair has slightly unequal branches of 6 and 7 segments. 
Segments are not protuberant, but their surfaces are distinctly rounded near distal extremity. 
Dense tufts of hairs are disposed on these rounded surfaces. 
Cirrus of third pair (Pl. XXIII, fig. 15) is slightly longer than that of 2™¢ pair, and has 
8 and 9 segments in the two branches. The anterior margin of each segment is distinctly 
rounded near the middle, and furnished with a group of hairs which does not form a tuft 
and is considerably less dense than that on the corresponding segments of the 2™¢ cirrus. 
With the exception of the last ones, the segments of both rami show a longitudinal row of 
small teeth between the hairs. These are slightly more distinct on the segments of the longer 
ramus and somewhat smaller on the first or basal segment of each ramus. A few. smaller 
teeth are disposed on the surface of most segments, forming indistinct rows, parallel to the 
main row along the margin. 
Cirrus of fourth to sixth pairs have the number of segments varying from 15 to 17. 
Greatest number of pairs of spines (Pl. XXIII, fig. 16) seen on anterior face of segments 
is 4. Of the group of hairs on exterior face near the extremity of the segments, one hair 
as a rule is much longer and stronger than the others. 
Penis very long, few hairs on the surface, and hardly any at the extremity; rather 
thick and stout at the basis, tapering towards the extremity, which is narrow, almost pointed. 
The specimen was collected at: 
Stat. 164. August 20, 1899. Lat. 1°42'.5 S., Long. 130° 47’.5 E. Depth 32 m. Bottom: sand, 
small stones and shells. It was found attached to a small piece of a brown stem, 
which, perhaps, is that of a species of Gorgonia. 
General Remarks. In outward shape this species comes nearest to B. galeatus 
Linn., from which it is distinct, however, by the horn-like transverse excrescences of the laterals 
and by the absence of the carino-laterals..] think this is the first instance of a species of 
Balanus really showing only four compartments 
25. Balanus proripiens n. sp. Pl. XXIII, fig. 17—21. Pl. XXIV, fig. 1—3. 
Carino-lateral narrow, rostrum elongate. Basis with a longitudinal furrow. Scutum with 
the articular ridge well-developed and reflexed. Tergum broad with a very wide spur. 
This new species is proposed for a form from rather deep-water (75—94 m.) that no doubt 
shows some resemblance to several species of Darwiy’s section B, but which, however, I think 
best to describe as a new species. It is represented by a single specimen: so as not to injure 
the specimen I refrained from investigating the structure of its parietes and basis. Its nearest 
relation, to judge by the shape of the opercular valves (the only parts of that species figured 
in Darwin’s Monograph), seems to be 2B. cymébiformis Darwin. 
The shape (Pl. XXIII, fig. 17) is elongate, lateral and rostrum, appear to creep 
along the thread-like stem of the Gorgonia. The shell is flattened laterally, the colour of the 
parietes and basis is white, with the exception of the carina, carino-lateral and adjacent parts 
of the lateral, which are pale-reddish, with slightly darker reddish longitudinal stripes. The 
Ioo 
