282 CEYLON PEARL OYSTER REPORT. 



large branch which repeats the structure of the stem. Over the whole surface of stem 

 and branches smaller branches are given off which also branch. 



The colour of the stem is greyish-white below, white above, while the smaller 

 branches are orange-coloured. The polyp-cups ai*e a dark purple-red, the tentacles 

 white. 



The surface texture of the specimen presents two quite different aspects. On the 

 bare stalk the surface has a granular appearance caused by the large number of very 

 small closely packed spicules which grow larger as the upper part of the stalk is 

 reached. On the branch-bearing part, and also on the branches, a stringy appearance 

 is produced by the larger spicules. 



The polyps occur in bundles of 4 to 8. The projecting spicules are usually red 

 throughout, but sometimes the lower part is yellow. The spicules are as follows : 



(a.) Of polyps and terminal tivigs. Yellow, or red, or partly yellow, partly red, 



covered by numerous small spines; Stutzbiindel, 2'6 millims. X 0'17 millim. ; 



polyp spicules, 0'03 millim. X 0'04 millim. ; others, 1 '5 millims. X O'l millim., 



17 millims. X 0'12 millim. 

 (>.) Of the stem, upper part. Similar to those of (a.), but the majority are 



colourless, or very faintly tinged with yellow. Spines more prominent 



and appear rougher, 

 (c.) Of the bare lower part of stem. Shorter, thicker, and with more prominent 



spines than (a.) and (&.). Spines more numerous and of greater 



diameter than the above. The spicules of (c.) measure 076 millim. to 



0'69 millim. X 0'16 millim., 0'42 millim. X 0'18 millim., 0'26 millim. 



X O'lO millim. Many of the spicules in (c.) are in the form of crosses. 



In several an X -shaped marking is seen as if the 4 arms of the cross were 



dovetailed into one another. 



Another specimen similar in appearance to the above has its branching restricted to 

 one plane. 



In its texture and flattened branches, &c. , it agrees with the above. The tentacles 

 are white, but owing to their state of retraction they do not show so much. The base 

 of attachment shows the rhizoid outgrowths frequent in Spongodes and allied genera. 



While these specimens do not rigidly correspond to the description given of 

 Spongodes rosea, the resemblance is too close to warrant separation. 



Localities : -Deep water outside pearl banks, Gulf of Manaar ; and Trincomalee. 



Spongodes armata, HOLM, var. ceylonensis, n. Plate I., fig. 6. 



This foliate divaricate colony consists of a cylindrical barren trunk, attached at its 

 base by means of rhizoid outgrowths to sand and fragments of Mussel shells, and a much 

 branched upper portion which forms an irregularly oval-shaped head. Everywhere 

 spicules project, thus giving a spiny appearance to the head portion. The little 

 violet coloured polyp heads contrast well with the orange coloured twigs. 



