Hapvpvon—The Actiniaria of Torres Straits. 467 
Corynactis hoplites, H. & S. 
Corynactis hoplites, Hadd. and Shackl., 18938, Proe. R. D.S., vut., p. 118. 
(Pl. XXX., figs. 1-4.) 
Form.—Column about twice as high as broad, smooth, pedal disk expanded ; 
tentacles, capitate, of two kinds, (1) marginal and (2) centripetal, situated on the 
disk, the latter in at least two cycles; mouth can be extended into a short tube, 
finely ridged internally. 
Colour.—Colour varied; (a) column burnt sienna-colour, with dark paired 
marks at the top of the scapus; tentacles translucent white, with a pink or white 
core at the swollen tip; mouth-cone speckled gray ; throat orange; (/) similar, 
with pinkish-brown tips to tentacles ; six pairs of marks on capitulum; (¢) trans- 
parent grass-green, with brown streaks; tentacles with transparent green tips. 
Dimensions.—Diameter of column about 8 mm.; height about 14 mm. 
Habitat.—Between Orman’s Reef and “The Brothers Island,” 6-7 fms., 
August 18, 1888; also on fringing-reef, Mabuiag, October, 1888. 
Body-wall.—The ectoderm, which is thrown into numerous folds in the 
specimen, consists of ciliated columnar cells with numerous oval gland cells, with 
unstained granular contents. The nuclei of the columnar cells are deeply stained, 
and are not irregularly placed in the cells, but appear in sections as a central 
band which lies nearer to the mesoglcea than to the periphery. There is a distinct 
layer of ectodermal muscle fibres. 
The mesoglea is homogeneous, stains deeply, and is of about the same 
average thickness as the ectoderm. 
The endoderm forms ridges between every two mesenteries. It contains 
scattered small oval cells of a yellow-colour. There is a slight diffuse endodermal 
muscle which becomes better marked as the sphincter is approached. 
The Sphincter Muscle-—Unlike C. viridis, which has no distinct sphincter 
muscle,* there is in C. hoplites a well-marked diffuse endodermal muscle (PI. xxx., 
fiz. 2). The mesoglea is thrown into numerous deep folds which are occa- 
sionally branched. 
Tentacles. —The ectoderm of the tentacles is very thick, at their extremities 
itis almost entirely composed of very long and narrow nematocysts each of which 
contains a distinct spiral thread (Pl. xxx., fig. 1). These nematocysts disappear 
as the disk is approached; the ectoderm also becomes thinner; and gland cells 
similar to those of the body-wall are found in the peripheral portion. The 
ectodermal muscular layer is well marked. The mesogleea is thin, ‘The endoderm 
* Cf, Haddon and Duerden, Trans. Roy. Dub. Soc., vi., 1896., Pl. vmt., fig. 11. 
Sud 
