434 Happon—The Actiniaria of Torres Straits. 
may be flat, or at times even conical; tentacles 48 in number in two cycles, those 
of the inner cycle being the longer; mouth oval, with twelve slight ridges, but 
no gonidial grooves; the whole animal is extremely delicate in texture. 
Colour.—Body translucent white, almost transparent; six vertical rows of 
brown, and six of white tubercles, all of which have a greenish grey apex sur- 
rounded by a narrow ring of cream colour; the inner cycle of tentacles trans- 
parent and free from colour except a slight tinge of pale pink in some lights, outer 
cycle similar, but with a bright orange mark at their base, and a dark violet-brown 
oval spot above it (Pl. xxim., fig. 5). 
Dimensions—Column, when fully expanded, 30 mm. high, and 17 mm. in 
diameter. 
Huabitat.—Albany Pass, Cape York, 10 fms. 
I made several sketches of this species when alive, but unfortunately the 
specimen was lost, and so I have no anatomical observations to offer. There can, 
however, be very little doubt as to the position of this form, and from the amount 
of contraction that can take place we may assume that the (? diffuse endodermal) 
sphincter muscle is fairly well developed. 
This species is certainly very nearly allied to the Actinia pretiosa of Dana from 
Fiji (U. S. Explor. Exped., Zoophytes, 1846, p. 187, Atlas, 1849, pl. 3, fig. 20: 
cf. M. Edw., Hist. Nat. Cor. 1857, p. 272, Andres, Le Attinie, 1884, p. 233); but 
I think it is a distinct species. 
CYSTIACTIS, M. Edw. 1857. 
Aliciidee with a column covered with simple vesicles. Tentacles of variable 
length, in two or three cycles. Sphincter muscle moderately well developed. 
Numerous perfect mesenteries. 
0. Eydouxi, M. Edw. 1857, Chile: C. Gaudichaudi, M. Edw. 1857, Rio Janeiro ; 
C. Reynaudi, M. Edw. 1857, Cape of Good Hope; C. tuberculosa (Q. & G.) 1833, 
Bass’ Straits; C. Eugenia, Duch. et Mich., 1866, W. Indies. 
THAUMACTIS, Fowler, 1889. 
Aliciide with irregular scattered complex vesicles, each of which when fully 
developed is prolonged into an elongated tubular process. Tentacles marginal, 
about twenty in number. Feeble, diffuse, endodermal sphincter. Ectodermal 
muscle fibres in capitulum and cesophagus. ‘Two cycles of perfect mesenteries ; 
no cesophageal groove. 
T. medusoides, Fowl., 1889. Papeete. 
