306 PERCY SLADEN TRUST EXPEDITION. 
Both are slightly roughened and compressed in section, the outside ones measure 0°3 
and the inside 0°2 mm. 
In addition to these, small secondary spines occur. These are sharp, triangular and 
compressed, and are irregularly scattered among the others. These secondary spines are 
not a common feature in this genus, this species and the variety of S. papillosa 
being the only ones known to me in which they are found; they occur more frequently 
in the genus Cirripathes. 
Locality. Ceylon, 34 fathoms (‘ Investigator’ Collection). 
& (2 4 
{sh 
5. Stichopathes regularis, sp.n. (Hig. 4.) 
A black, evenly coiled stem 80 cm. in length, tapering to a point; the base and attach- 
ment are missing. The corallum has a width of 1:25 mm. at its widest part, the central 
canal being one-third the total diameter. 
The polyps are arranged in a well-defined line on the outside of the coiled stem and 
are separated from one another by regular intervals of 1 mm. ‘They are white in colour, 
circular, and average 1 mm. in diameter. The arms are short, the lateral ones being 
set at a lower level than the rest. The mouth is round and is placed on a small 
prominence. 
The spines are of one kind only, arranged with great regularity in twelve straight 
lines. They are bluntly conical, slightly roughened at the tips, and stand at 
right angles to the corallum. ‘Those on the outside of the spiral are a trifle larger 
than those on the inner side, averaging 0°2 mm. for the former and 0:14-0:17 for the 
latter. 
Localities. Salomon Atoll, Chagos, off the entrance to lagoon, 65 fathoms. Ceylon, 
35 fathoms (‘ Investigator’ Collection). 
