M5 
has a sagittally elongated or rounded mouth. Lateral tentacles equal in length 
(0.6 mm.); sagittal tentacles 1 mm., inserted at a much lower level. Interpolypar 
distance 2 mm. The oral cone may be constricted at the base of the lateral 
tentacles. 
7. Stichopathes ceylonensis T. & S. 
0 
Stichopathes ceylonensis T. & S. THOMSON & SlMPSON, On the Antipatharia (Report to the 
Government of Ceylon on the Pearl Oyster Fisheries of the Gulf of Manaar. Suppl. Rep. 25, 
p. 93—106). 
Stat. 267. 5° 54' S., I32°56'.7E. Arafura-sea. 984 M. Grey mud. 1 spec. 
I he height of this colony is 10 cm., but the stem is 20 cm., measured along the axis. 
I he basal plate is of an irregular shape, with some wartlike knobs, probably caused by the 
irregularities of the underground. The first 4 cm. are curved; they are succeeded by three 
fourth coil ot a smistrorsal spiral, with a diameter of 1.5 cm. 1 hen again a curved part of 
3.5 cm. comes in and the rest is 1.5 coils of a sinistrorsal spiral with a diameter of 2 cm., and 
a distance of 2 cm. between the coils. The basal diameter of the stem is 800 u. and gradually 
diminishes towards the blunt top, which has a diameter of 300 p even at a distance of 4 mm. 
from the top. The spines (fig. 201) are arranged in 3(—4) longitudinal rows, which alternate 
in a straight or slightly slanting quincunx (fig. 201). Their mutual 
distance is 750 — 800 p. at the base of the colony, and increases 
untill 900 p., even at a rather small distance from the basal part. 
The spines are blunt and triangular (fig. 201) with their distal side 
almost at right angles with the axis; double-topped spines may be 
found occasionally. The length of the spines is 120—150 p. on the 
non-polyp-bearing side of the axis. At the base of the colony the 
spines are rarely in an undamaged condition; their length is here 
± 100 p„. The surface of the spines is smooth and their concentric layers are very conspicuous 
(fig. 201). I he polyps (fig. 202) are arranged in a single series with an interpolypar distance 
of more than 2 mm. The sagittal tentacles are 1.5 mm. long; the 
lateral ones 1 mm.; the sagittal ones are inserted at a slightly 
lower level than the lateral tentacles. The oral cone is dome¬ 
shaped, somewhat oval with a largest diameter of 0.6 mm. 
(in the sagittal direction!). The mouth is very much sagittally 
elongated, with a greatest diameter of 0.2 mm. Young polyps 
occur between the adult ones: the cross-grooves between the 
o 
polyps and the longitudinal groove along the back of the axis 
are clearly visible. The tentacles are directed towards every side, leaving the mouth uncovered 
(fig. 202 < 5 ), or they are crowded into a distally directed group, covering the oral cone (fig. 202 a). 
1 here is no difference in length between the distal and proximal lateral tentacles. — I have 
thought about a possible identification of this specimen with Stichopathes abyssicola R. but the 
type of polyp is too unlike each other, while the spines are also too different to permit a 
SIBOGA-EXPEDITIE XVII. tQ 
Fig. 202. Stichopathes ceylonensis T. & S. 
Polyps: a profile; b oral view; u, i 7.6 
Fig. 201. Stichopathes ceylonensis 
T. & S. Spine (52 X) and arran¬ 
gement of the spines (7.6 X)- 
