17 
different) and the only differences that I can notice are (1) that, instead of 
all the costz being equal, those of the last cycle are much smaller than those 
of the other cycles (which are all of one size), and (2) that the columella is a 
little larger, in this species. 
Seeing how variable the coste of Deltocyathus may be, and how easily the 
columella may be affected by more or less fusion with the pali, I doubt whether 
these differences are specific, and I believe that the form here described may 
prove to be a variety of Deltocyathus italicus (Mich.). If this should be really 
so, we shall have another connecting link between the West Indian region, the 
Azores region, the Mediterranean basin and the Seas of India, although, since 
Deltocyathus italicus was dredged by the “Challenger” in the Arafura Sea, 
this will be no essentially new discovery. 
Corallum discoid, free, with a small central scar. Coste. in their distal 
half, covered with spiniform granules; those of the first three cycles are 
indistinct near the scar, but become sharply salient near the circumference ; 
those of the last cycle, which have a ragged appearance owing to the size and 
abundance of their granules, can be distinguished only near the circumference, 
and are smaller and less salient than those of the other cycles. 
Septa and pali profusely ornamented with spiniform granules. The septa 
are in six systems and four complete cycles, but in some of the half-systems a 
fifth cycle is developed. 
The septa of the first cycle are large and exsert, and each, with its palus, 
remains perfectly independent of all the other septa and pali. 
The septa of the last cycle are small, independent, and without pali. 
The septa of the second and third cycles (and those of the fourth also, in 
the half-systems in which a fifth cycle occurs) are as large as those of the first, 
but their pali (which are larger and further from the centre than the pali of 
the first eycle) soon unite to form “deltas”: these « deltas,” owing to the size 
and abundance of their granulation, have a lace-like appearance, 
Columella sunken, concave, spongy-papillose. 
Colour of the living corallum, madder-tinted. 
Diameter of corallum about 18 millim. 
A single specimen from the Andaman Sea, 172-303 fms. 
v. THECcocyatuts, Edw. & H. 
10, (?) Thecocyathus cinticulatus, n. sp. Pi. ii. figs. 5, 5a. 
This species resembles Thecocyathus cylindraceus and lxevigatus Pourtalas 
(Il. Cat. Mus. Comp. Zool. No. IV. 1871, pp. 13, 14) in their somewhat 
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