476 Happon—The Actiniaria of Torres Straits. 
Tentacles—Both the endodermal and ectodermal musculature of the tentacles 
is weak. ‘The mesoglcea is of similar structure to that in the body-wall. There 
appear to be no zooxanthellz present. 
Mesenteries.—There are three pairs of directives in the specimen examined, 
corresponding to the three grooves. T'wo of these are close together, the third is 
at the opposite side of the cesophagus; but it is separated from one of the pairs of 
directives by about ten pairs of perfect mesenteries, and on the other side by 
about five pairs. Some of the ten pairs are, however, closer together than the 
five pairs. The arrangement of the imperfect mesenteries between the perfect 
pairs is quite irregular. 
I place the two following species as a sort of appendix to the family Discoso- 
midee, as neither can be placed in its appropriate genus until it has been examined 
anatomically. 
‘¢ Discosoma nummiforme,” Leuck. 
Mr. Saville-Kent, in ‘‘The Great Barrier Reef” (p. 150, chromo pl. iu., 13), 
allocates to the above species a small Discosoma, 50 mm. (2 inches) in diameter, 
which he found in Torres Straits and on the Queensland coast. The pentagonal 
disk and the column are usually a rich purple-brown, and the almost sessile 
spheroidal tentacles are for the most part of a brilliant emerald green; but some, 
usually the centripetal ones, are of a purple-brown. 
I do not know this form, nor do I think, from Saville-Kent’s description, that 
it is D. nummiforme ; it may be the young of S. Haddonz. 
‘“¢ Diseosoma rubra-oris,” S.-Kent, 1898, ‘‘ The Great Barrier Reef,” p. 151, chromo 
pl. ii., fig. 12. 
‘‘The disk is more symmetrically ovate or circular, and the tentacles, while 
sessile and spheroidal, are mounted on projecting rugz of the disk.” The colour 
is various shades of dark and yellow green, disposed in alternate triangular bands 
from the periphery to the centre; the oral cone is of a brilliant magenta hue. 
Family.—Ruopactipm, Andr. 
Phyllactinine (pars), Klunz., 1877. 
Rhodactide, Andr., 1583, p. 282. 
Stichodactylinz, with a smooth body, greatly expanded oral disk, and tenta- 
cles of two kinds. The margin is furnished with minute tentacles of the ordinary 
kind, arranged apparently in a simple cycle, while upon the surface of the disk, 
