174 THE VOYAGE OF H.M.S. CHALLENGER. 
Extreme height of the largest specimen, 57 mm. Extreme breadth, 65 mm. Shorter 
diameter of the calicle, 28 mm. 
Eleven specimens. Station 163. Off Twofold Bay, New South Wales. 120 
fathoms. 
Flabellum transversale, u. sp. (Pl. VI. figs. 6, a). 
The corallum is dense and heavy; it is elongate compressed conical in form, with 
rounded surfaces and without lateral ridges. The lateral borders make with one another 
an angle of about 30°. There is a short pedicle, with a small scar of attachment 
twisted to one side. The entire wall of the corallum is marked by deep curved trans- 
verse sulci and rounded ridges formed by suecessive intervals in growth. These are 
hardly sufficiently marked in the figure. Very numerous fine costal strive extend over 
the whole surface. The calicle is oval in form, the edge of its margin is a little 
irregular, but not toothed by the septa, the summits of the two axes are nearly on the same 
level. There are in the single specimen, eighteen complete septa and eighty-eight septa 
in all, which are of three well-marked different sizes, with a few of a fourth size which 
apparently were about to have become complete had growth proceeded. The septa are 
continued to the margin of the calicle. They are stout and straight, with abundant 
fine pointed granules on their surfaces. The fossa is moderately wide, and extends down 
for about one-third the depth of the calicle, where it is bounded by the usual columella. 
The lower part of the free margins of the septa are finely serrate. 
This coral seems nearly allied to Professor Semper’s Flabellum irregulare, but 
differs from it in its greater irregularity of shape, its bent pedicle, and more widely open 
fossa. 
Height of the single specimen, 35 mm. Long diameter of the mouth of the calicle, 
23 mm. Short diameter, 14 mm. 
Station 162. Bass Straits, Australia. 38 fathoms. A single specimen only. 
Flabellum curvatum, n. sp. (Pl. VI. figs. 3, a-d). 
The corallum is white, and is trumpet-shaped, bent and twisted, and compressed. 
It is attenuate below, being drawn out gradually into a pedicle, which is usually bent 
sharply to one side, and in one specimen (that figured), has a small fragment of stone 
attached to it. Besides the bend in the pedicle, the corallum is also always much curved 
in the plane of compression. The lateral regions of the wall are evenly rounded, and 
the lateral surfaces are inclined to one another at an angle of about 50°. The entire 
surface is covered with an opaque white epitheca, due to decomposition of the exposed 
dead outer surface. It shows transverse accretion folds, and is marked all over by 
1 Semper, lc, Z. f. Wiss. Zool., 1872, p. 242. 
