192 THE VOYAGE OF H.M.S8. CHALLENGER. 
formed by the coalescent branches and branchlets are often as much as 5 em. wide, and 
the thickness of the fronds and branches throughout is uniformly about 5 mm. The 
broadened extremities of the branches trend horizontally, and become divided vertically 
into parallel branchlets, which often remain laterally fused, and give a ribbed appearance 
to the lower part of the frond. The branchlets in their free portion are sometimes as 
much as 2 em. long, though they are generally much shorter and irregular, somewhat 
compressed, about 3 mm. thick, slightly tapering, and rounded at the end; in developing, 
these branchlets elongate, curve outwards, become horizontally directed, and broadened 
out into thin, compressed, vertical fronds, from 2 to 5 em. wide, which become in turn 
divided vertically into numerous irregular, small, parallel branchlets ; these fronds either 
coalesce laterally with other fronds, or fuse with opposite ones at their extremity, thus 
forming bridge-like pieces. The surface of the coenosteum is nearly smooth, being finely 
and evenly reticulated. The pores are small and scattered irregularly, often scarcely dis- 
tinguishable over large areas of the ccenosteum ; the gastropores are about 0°25 mm. in 
diameter, and. rather wide apart; the dactylopores are very minute and generally 
very numerous, less abundant on the apical parts of the branchlets and on the 
basal parts of the colony. Ampulle developing as special cavities in the superficial 
meshwork of the coenenchyma; often crowded, about 0°75 mm. in diameter within, 
searcely raised above the general surface, on which they are seen as small white 
spots or vesicles, which are about 0°5 mm. in diameter, the centre being generally 
pierced by a small pore. 
This species is close to the Millepora tortuosa, from the Fiji Islands, but can easily 
be distinguished from it. I have named it in honour of Mr. John Murray, whose 
observations on the living zooids of Millepora so materially aided Professor Moseley 
in his researches on the genus. 
On dry specimens which have been kept for some time, and on which ampull occur, 
it is easy to demonstrate their presence by the comparatively large pits which are formed 
over the surface by the abrasion of the thin, upper layer which covers them, and which 
are easily distinguishable from the minute pores of. the cyclosystems. 
Locality,—Samboangan, Philippines. 
4, Millepora ramosa, Pallas. 
Millepora alcicornis, var. ramosa, Pallas, Elench. Zooph., p. 261. 
Millepora ramosa, Dana, Zoophytes, p. 544. 
Two specimens of this species are in the collection. The main stems are large and 
strong, being as much as 2°5 cm. in diameter at the base, and the branches rise to a 
comparatively great height. The cyclosystems are generally well marked ; the gastro- 
pores are slightly larger than the dactylopores, but both are small. 
