ALCYONAKIANS. BRIGGS. 73 



The colour of the colony is cream. 



Locality. Fifteen miles N. 35 E. of Saddle Hill, New 

 South Wales, 34-35 fathoms. 



Distribution. Hitherto recorded only from eleven miles 

 east of Broken Bay, New South Wales (Thomson and Mac- 

 kinnon). 



MOPSEA FLABELLUM, Thomson and Mackinnon. 



Mopsea flabellum, Thomson and Mackinnon, Mem. Austr. 

 Mus., iv., 13, 1911, p. 676, pi. Ixiii., figs. 1-3, pi. Ixvii., 

 fig. 6, pi. Ixxi. 



The collection contains two incomplete branching speci- 

 mens, the characters of which agree in detail with Thomson 

 and Mackinn oil's description of Mopsea flabellum. The 

 larger of the two colonies is 24 cm. in height. The basal 

 attachment is lacking. The branching is dichotomous and 

 strictly confined to one plane. The branches, though 

 slender, maintain an almost uniform diameter of about 

 2 mm. throughout their length. 



The lower portions of the stem and branches are devoid of 

 ccenenchyma, and the axis, which is about 3 mm. in diameter, 

 is composed of creamy -white calcareous internodes with well 

 marked longitudinal fluting, and brown-coloured horny nodes. 

 In the twigs, however, the colour of the calcareous joints is 

 deep orange. 



The club-shaped polyps are arranged in close-wound 

 spirals all over the branches. Their armature consists of 

 about eight longitudinal rows of overlapping spicules. A 

 low operculum is formed of eight plates similar in appearance 

 to the scales with which the polyps are covered. 



The superficial spicules are flat, yellow-coloured, circular, 

 8-shaped, irregular scales -262 x-105 mm. ; -210 x-157 mm.; 

 192 x-061 mm. ; -175 x-175 mm. Each scale is smooth or 

 bears a few simple warts ; the margin is deeply dentate or 

 serrate. The spicules of the ccenenchyma are (1) yellow- 

 coloured spindles with a few large warts -175 x -052 mm. ; 

 157 x -052 mm. ; -122 x -035 mm. ; and (2) small irregular 

 bodies -087 x -052 mm. ; -070 x -035 mm.; -052 x -052 rnm. 



The colour of the colonies is orange-brown ; the polyps 

 yellowish. 



Locality. Thirty-six miles S. 58 W. of Cape Wickham, 

 King Island, Bass Strait, 72-80 fathoms. 



