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segments are not very elongate, the terminal ones being only thrice as long as broad. Near 
the extremity the inner face of each segment is somewhat swollen; this swollen part is furnished 
with a group of longer hairs, representing the 2 to 3 pairs of hairs seen on the inner 
face of the segments of the other cirri; some of these hairs are rather long, some medium- 
sized, some short; each segment, moreover, bears a small group of not very long hairs on 
the outer face near the extremity. Finally, all the segments of both branches, with the 
exception of the 7 to g last ones, are furnished, on the somewhat swollen part of the inner 
face near the extremity, with a row of minute tooth-like pointed spines, which point upwards, 
and which are strongest on the lower segments of the anterior ramus. The second segment of 
the pedicel of this cirrus shows a group of 3 to 4 such teeth on the inner face near the 
extremity. Outer face of lower segments of both branches rough through short spines being dis- 
posed along the margin. 
The cirri of the fifth and sixth pairs have the rami very elongate and composed 
of very numerous segments. Each segment bears a group of 3 to 5 delicate hairs on the 
outer face, mear the extremity. The number of pairs of hairs arranged along the inner face 
of the segments is two in the lower and three in the upper segments. Only here and there, 
a fourth pair of extremely minute hairs could be seen. The teeth-like spines on the swollen 
parts of the segments of the 4 cirrus are represented on the 5 and 6 cirri by much 
smaller spines of the same shape. The outer margin of the lower segments of the 5‘ and 
6th cirrus is distinctly rough, being furnished with one or more longitudinal rows of extremely 
small teeth-like spines which point upwards. 
The penis is very long, distinctly ringed, tapering towards the extremity. A group of 
short hairs is situated at a short distance from the extremity, very few hairs only are scattered 
over the surface. 
The only specimen of this species collected during the cruise of H. M. S. “Siboga”’ 
was taken at Station 301. Numerous and larger specimens of the same species were found 
by me in a collection of Cirripedia made during the fishing trips of the Inspection-Steamer 
“Gier”’ in the Western half of the Malay Archipelago. The accurate positions of these places 
are as follows. 
Stat. 301. January 30, 1900. Lat. 10°38'S., Long. 123°25'.2 E. Pepela-bay, East coast of Rotti- 
island. Depth 18—45 m. Bottom: mud, coral, and Lithothamnium. 
Hs M>s: -Gierz, N° 14) Experiment 45) December 16,1908. batsam2n5 bono m monsoon 
Depth 25—35 m. Bottom: mud. 
Ho MES. “Gier N° 14) Expenment 7. December 7,m190omlbeatqna 24S lon cemn toma. aa 
Depth 27—33 m. Bottom: mud. 
Genus Hexelasma nov. gen. 
Compartments six; carina, carino-lateral and lateral compartments with alae, but without 
radii, the rostrum having neither radii nor alae. Parietes not porose and without longitudinal 
ribs on their inner surfaces; basis membranous. Opercular valves sub-triangular. 
Mouth with the labrum not notched in the middle; mandibles with 4 to 5 sharply 
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