263 



first infolded and then the whole is withdrawn. There is a distinct collaret 

 of two to three rows of curved spindles surmounted by eight triangles. Each 

 triangle is formed by two long, slightly curved spindles, touching for a short 

 distance on their convex sides and based by a smaller almost straight spindle. 



The general colour of the colony is almost brick-red but the polyps are 

 white. 



The spicules of the general coenenchyma are red but those of the antho- 

 codire are colourless. The following are the more typical forms with measure- 

 ments in millimetres : — 



(a) Coenenchyma; (1) Foliaceous clubs. From one end of a thick central 



shaft there extend one to three irregularly warty 

 projections and from the other a foliaceous expan- 

 sion. The latter is variously shaped and thins off 

 towards the edge. In some cases it is perfectly 

 smooth but in others a few warts occur. Dimen- 

 sions, 0-6 X 0-3 ; 0-5 x 04 ; 04 x 035 ; 0-25 x 0-2. 

 (2) Warty spindles wdiich are sometimes branched, 

 0-5 X 0-1 ; 0-4 X 0-1 ; 03 x 0-08 ; 02 x 006. 

 (h) Anthocodite : Small thick spiny spindles, 0*2 x 0-025 ; 0-15 x 0-02. 

 This species approaches very closely to Ridley's variety cinerea. 

 Locality : Andamans. 



Previously recorded from Port Curtis, Queensland, 5-10 fathoms, Ridley ; 

 Torres Straits, Wright and Studer (" Challenger "). 



GENUS PSAMMOGORGIA, Vcrrill. 



Psammogorgia ridleyi, n. sp. 



Plate 11. fig. 5 ; Plate IX. figs. 10 (a), 10 (1)). 



This species is represented by a beautiful upright colony 26 -5 cm. high and 

 12 cm. in breadth. It is attached to a piece of rock over which there spreads 

 a thin filmy base covering cirripedes and madrepore coral. From this reptant 

 base there arise two conical structures which give origin to two main stems. 

 The smaller of these is 14 cm. high and gives off" branches on two sides in one 

 plane. This colony is devoid of coenenchyma and is overgrown by a sponge. 

 The larger, which constitutes the diagnostic specimen, is branched almost in one 

 plane. Only one branch diverges, and it ultimately converges to the plane of 

 ramification. Secondary branches arise in the same manner from the primaries. 

 The tips of the branches and twigs are slightly club-shaped. The main branch 

 has been broken, and 70 mm., at the tip have been re-grown, but with a smaller 

 diameter. 



