6 SYDNEY J. HICKSON. 
at the nodes and 0°6 mm. at the internodes. The ramification is irregular and in all 
directions, but the branches in all cases arise at an acute angle from the calcareous 
internodes. The ccenenchym is very thin, and is absent from a great many of the 
branches. The terminal branches are about 0°3 mm. in diameter at the base, and 
attenuate distally to a very fine point. 
The internodes are 6 mm. long. Here and there shorter internodes occur, but 
on the whole the length of the internodes is fairly constant. The calices are quite 
irregularly scattered. Usually a group of four or five calices situated at intervals of 
1 or 2 mm. stands apart from other groups, but as a great many calices have dropped 
off, this grouping may be the result of injury. 
The ecalices are bent at an acute angle to the axis; the outside measurement is 
about 0°65 mm. The diameter of the calyx at the base is 0°3 mm., and at the crown 
0°4mm. The spicules of the coenenchym are flat, tuberculated spindles, varying 
from 0°2 mm. to 0°1 mm. in length (fig. 12a). On the neck of the calyx similar 
spicules, somewhat bent, are arranged in fourteen or fifteen horizontal rows. The 
spicules of the crown and of the backs of the tentacles are often expanded at one end 
to form a triangle (fig. 12b). 
CERATOISIS (PRIMNOISIS) ANTARCTICA. 
(Plate II., figs. 13, 14, 15.) 
Tsis antarctica, Studer, MB. Ak. Berlin 1878, p. 662. 
Locality :-—(1) McMurdo Bay, February 8, 1902, 96-120 fathoms ; (2) McMurdo 
Bay, February 28, 1902, 20 fathoms. 
The two specimens which may be attributed to this species are broken from their 
base, and each measures about 50 mm. in height. It is probable that they were torn 
from the same colony. The branching is quite irregular and shrubby. The internodes 
are about 6 mm. in length, but vary a good deal more than in C. delicatula. The 
thickest internode in the specimen is about 0°9 mm. in diameter. The calices are 
numerous, and situated at intervals of about 2 or 3 mm. on the branches, but gathered 
close together in clusters near the extremities. I cannot recognise any spiral arrange- 
ment of the calices such as that described for the type by Professors Wright and Studer 
(14). Hach full-grown calyx is from 1 to 1°5 mm. in height and stands out almost at 
right angles to the axis. 
The spicules of the ceenenchym are flat spindles about 0°3 mm. in length (fig. 14a), 
and those at the base of the calices are bent. The calices are protected by overlapping 
scales of very irregular form and size, but usually straight on one side, convex on the 
other, and not exceeding 0°3 mm. in length (fig. 14b). The scales on the back of the 
tentacles are all horizontally placed (fig. 15). 
The type of this species was obtained by the ‘Gazelle’ in 60 fathoms off 
Kerguelen (Studer (10), p. 661), and subsequently specimens were obtained by the 
‘Challenger’ in 310 fathoms off Prince Edward Island. I have compared the 
