288 CEYLON PEARL OYSTER REPORT. 



very slightly and have a diameter of 1 millim. They are often separated about 

 1 millim. from one another. The verruca is a truncated cone, in some cases like a 

 widely open crater, in other cases with eight spiculated lobes projecting inwards like 

 small sepals in an almost open bud. A low-power view shows that there are eight 

 opercular coverings formed from spindle-shaped spicules. 



Careful dissection of the included polyp, under low power, shows a cylindrical body 

 with eight vertical external muscle-strands and with a low conical apex. Around the 

 base of this apex there seems to be a ring of horizontally disposed spindles in two 

 or three rows, and from this there arise the eight triangular converging opercular 

 coverings, with spicules more or less at right angles to those of the basal ring. But 

 the specimens were extremely brittle, and the gentlest touch of the dissecting 

 needle almost invariably shivered the microscopic architecture. 



The extremely calcareous sclerogorgic axis is densely packed with more or less 

 spindle-like spicules embedded in the matrix of horny fibres. It varies from 1 millim. 

 to 2 millims. in diameter. 



The ccenenchyma spicules are mostly minute spindles with numerous regularly 

 arranged blunt tubercles; a common measurement is - l millim. to 0"125 millim. in 

 length by about 0'025 millim. in maximum thickness. There are also minute warty 

 double clubs or capstans, with a very short middle zone and broad disc-like ends ; 

 they measure about 0-025 millim. by 0*02 millim. Some of the spindles have very 

 few tubercles. 



We have given these details to supplement the previous descriptions of Suberogorgia 

 verriculata, to which, we believe, these specimens must be referred. 



Locality : Deep water off Galle. 



Another specimen is 281 millims. in height and 134 millims. in maximum breadth, 

 but this does not represent the full size of the specimen, as a part has been 

 broken off the main stem. The branching is confined to one plane, and there is a 

 very complete anastomosis of the branches, thus giving rise to a fine reticulate fan- 

 shaped colony. The chief branches rise at an acute angle and are directed upwards, 

 and assume a position roughly parallel to the main stem. The tips of the branches 

 are clavate. 



The polyps come off from all sides of the stem and branches and appear to be 

 spirally arranged in some parts. They are completely retractile, and in the specimen 

 they are all withdrawn within the small verrucse. 



The spicules are small spindles with prominent rough warts, larger spindles and 

 minute double wheels or capstans. The measurements length by breadth in milli- 

 metres are as follows : 



Capstans, 01)37 X 0-02 ; 0'035 X 0"02 ; 0"03 X 0"02. 



Slender spindles with few warts, 0-09 X 0-018 ; 0"15 X 0"02 ; 0-10 X 0"03. 



Other spindles, 0"10 X 0"03 ; 0"12 X 0"037 ; 0-16 X 0045. 



The axis measures 6 '4 millims. in diameter at the base. 



