156 THE VOYAGE OF H.M.S. CHALLENGER. 
22. Madrepora laxa, Lamarck. 
Madrepora lawa, Lamarck, Hist. Anim. sans Vert., ii. p. 280, 1816. 
Milne-Edwards and Haime, Cor., ii. p. 146. 
” ” 
A portion only of a specimen was obtained. The species is very close to Madre- 
pora pocillifera, but seems to be sufficiently distinguished by the nature of the calicles, 
which are tubo-labellate, much thicker and stronger, especially on the under side 
of the cup, not oblique or fragile, but becoming verruciform, especially towards 
the basal parts of the branchlets. The branches are often short and thick, with many 
proliferous branchlets crowned by thick and broad apical cups. The surface is shortly 
striate, dense and echinulate. 
Locality.—Reefs, Fiji. 
23. Madrepora aspera, Dana. 
Madrepora aspera, Dana, Zoophytes, p. 468, pl. xxviii. fig. 1. 
The specimens of this species agree closely in essential features with the description 
given by Dana, whose specimen was a fragment 3 inches in height. Those in the 
collection are large and much branched specimens, and show very clearly that though 
the apical parts are porous in texture, the basal portions are dense and firm. The lateral 
ealicles are very unequal and rather crowded, many very small narrow labellate ones 
being’ placed between the larger, which are broadly labellate ; the aperture of the cell 
where it joins the branch is always small. Dana characterises the cells as being quite large, 
but a reference to his figure of a branch, natural size, will show that the term must be 
applied to the broad lip and not to the aperture of the cell where it jos the branch. His 
measurement for the width of the immersed cells below is half a line, but at the basal 
parts in large specimens it is much smaller, and in many parts the cells are seen to be 
quite minute openings over the surface of the corallum. 
The fragile lips of the lateral calicles, which are very prominent above and erect or 
divaricate, are very easily destroyed, the narrow cells becoming more or less obsolescent ; 
while the stronger basal parts of the larger calicles give a rough and ragged appearance 
to the branches. 
The species is very close both to Madrepora pocillifera and to Madrepora laxa. 
In Madrepora pocillifera the calicles are quite oblique, more open and cochleariform, 
larger and more crowded; in Madrepora laxa the differences seem to be less marked, 
but the ecalicles are shorter, not fragile, tubo-labellate with a thickened lip which is not 
flattened, but almost verruciform in many parts. 
Locality.—Mactan Island, Philippines. 
