Lichinoderm-Fauna of Ceylon. 221 
9. Astropecten, sp. 
A small, not very well-preserved specimen, which seems to 
be more closely allied to A. granulatus, M. & Tr., than any 
form I have had the opportunity of examining. 
OPHIUROIDEA. 
10. Ophiocoma erinaceus. 
11. Ophiocoma scolopendrina. 
These two species appear to be both present in the collec- 
tion ; and it is interesting to note that what is ordinarily re- 
garded as the general appearance of the one is to be found 
associated with the structural characters of the other—speci- 
mens with darker and lighter ring-marks on the spines pre- 
senting the swollen upper spines, while others in which the 
swelling of the upper spines is but faintly marked have the 
interbrachial spines on the lower surface of the disk almost, 
though not quite, bare of granules. 
12. Ophiocoma brevipes. 
13. Ophiocoma pica. 
14. Ophiothrix nereidina (?). 
Till the species of this genus have undergone some revision 
or been rearranged in smaller subgroups, there will often be 
considerable doubt as to the specific identity of a form not re- 
presented by several specimens. 
15. Ophiomastia annulosa. 
Although this species has been represented in the British 
Museum by specimens of considerable size, there has never 
yet been obtained one so large as that which we owe to the 
liberality and care of Dr. Ondaatje. 
One specimen, which is nearly perfect, has its longest arm 
300 millim. in length, while the disk is 28°5 millim. in dia- 
meter; another specimen, a good deal injured, has its disk 
35 millim. in diameter. Here we can only guess at what the 
arms were or might have been: in the former specimen the 
arm, at a distance of 150 millim. from the disk, was 3 millim. 
wide, while it was 4°5 millim. wide at its base; in the latter 
specimen the arm, 5 millim. wide at the base, was 4 millim. 
wide at a distance out of 150 millim. It is quite possible 
