164 THE VOYAGE OF H.M.S. CHALLENGER. 
10 mm. wide and 4 to 5 mm. thick, which are coalescent so as to form a broad and thin 
lamina with numerous meshes. The under side, where the flattened, coalescent branches 
and branchlets are seen to form an irregular trellis-work with meshes of different sizes 
and shapes, is almost entirely destitute of calicles, except a few immersed ones; some 
large and long calicles oceur, which spring from the compressed edges of the branches 
and give rise to small branchlets, which become closely appressed to, and ultimately fuse 
with, the adjacent branches. The upper side is covered throughout with closely placed 
clusters of very long, proliferous calicles, which are sometimes in groups of five or six, 
and between which occur a few shorter and immersed ones. The calicles of the clusters 
are tubiform, about 15 mm. long (often more or less), curved, tapering and irregularly bent, 
from about 3 to 4 mm. wide at their base and 1°5 mm. at their apex, and many of them 
carry two or three short and small, lateral calicles. At the outer, free edges of the 
corallum the branches are not elongated, but short and rather thick, and the calicles are 
short and thick proportionately and more closely placed, but never crowded. Six septa 
are present, and sometimes there are rudiments of a second cycle. The caenenchyma is 
dense, and the surface very closely and finely echinulate. In many places, and chiefly 
between the coalescent branches, the surface becomes reticulate or finely fissured, so as 
to present a worm-eaten aspect. 
In its mode of growth this species bears marked resemblance to Madrepora 
granulosa, Milne-Edwards and Haime, but its other characters easily distinguish it. A 
large specimen and a few fragments were obtained. 
Locality.—Tahiti. 
46. Madrepora hyacinthus, Dana. 
g. 2. 
Madrepora hyacinthus, Dana, Zoophytes, p. 444, pl. xxxii. fi 
A single very large, shallow, vasiform specimen, about 40 cm. in diameter, is in the 
collection, and it agrees in every particular with the excellent description given by Dana. 
The branches are frequently, though loosely, coalescent ; and often towards the centre of 
the vase the branchlets become very short and proliferous. The vase is very irregular in 
outline, owing to the unequally grown branches. The apical calicles are very uniform in 
size, from 2°5 to 3 mm. in diameter. 
Locality.—Levuka, Fiji. 
47. Madrepora conferta, n. sp. (Pl. X. figs. 3-8c). 
Corallum flattened, about 2 to 3 cm. thick; branches very closely packed and much 
divided, densely and intricately coalescent, with narrow, elongated meshes, but with the main 
branches remaining distinguishable. On the under side there are numerous, coalescent 
