424 Hapvpon—The Actiniaria of Torres Straits. 
ACTINIOIDES, H. & S. 
Actiniidee with more or less prominent suckers on upper portion of column; 
capitular margin with conical acrorhagi; diffuse or feebly circumscribed endo- 
dermal sphincter muscle. 
This genus bears somewhat the same relation to the genus Actinia, that 
Condylactis does to Anemonia. 
A. Divoniana, Hadd. & Shackl., 1893, p. 126. 
A, Sesere, Hadd. & Shackl., 1893, p. 126. 
A. Spencert, Hadd. & Duerd., 1896, p. 159. 
A, Papuensis, n. sp. 
Actinioides Dixoniana, H. & S. 
Actinioides Dixoniana, Hadd. and Shackl., 1893, Proc. R. D. 8. vu, p. 126. 
(Pl. XXII, fig. 6; Pl. XXVIL., figs. 1, 2.) 
Form.—Column, covered with vertical rows of sucker-like verruce ; capitular 
margin provided with large conical acrorhagi; tentacles in two cycles, no¢ in 
multiples of six; sphincter muscle feeble but slightly circumscribed. 
Colour.—Column, various shades of greenish grays and browns in vertical 
lines; tentacles, olive-brown, banded with greenish white or grey on oral aspect ; 
acrorhagi, yellowish ; disk, dark greenish brown, with white markings; lips of 
mouth with white radial lines, a brown ring round the mouth. 
Dimensions.—Diameter of corona of largest specimen, 3l1mm.; length of 
tentacles, 10 mm. 
Habitat.—F ringing reef, Mabuiag. 
Body-wall.—Very similar in character to the following species, but mesoglcea 
thicker, and endoderm thinner in proportion to ectoderm. Endodermal muscular 
layer with well developed mesoglceal plaitings. Neither warts nor ridges appa- 
rent in transverse sections. The marginal spherules or acrorhagi (Pl. xxvu., 
fig. 1, acr.) are composed principally of the greatly thickened ectoderm, the cells 
of which are very tall and slender. 
The short diffuse endodermal sphincter muscle consists of about four simple 
or slightly branched plaits of mesoglcea, flanked by a few small, simple plaits ; 
the mesoglcea is also thickened in this region. 
Tentacles with a slight transverse fluting. ‘The ectoderm and endoderm are very 
thick, but the mesogloea is very thin, Ectoderm similar to that of A. Papuensis, 
