204 CEYLON PEARL OYSTEE REPORT. 



The mouth is ventral, and is surrounded hy a small brim of papillae. There are no 

 anal teeth. 



Deposits consist of two kinds : 



(1.) Closely packed tables having, in the older specimens, a large central hole and 

 about eight smaller peripheral holes. This is surmounted by a spire having 

 four upright bars. There is one tier of horizontal bars. The spire terminates 

 in a round top having numerous spines (figs. 47 and 49). 



(2.) Knobbed "buttons," having generally three pairs of holes (fig. 48). 



The tables in the smallest specimen are much better developed than in the older 

 specimens. The buttons in the youngest animal have about five pairs of holes, whilst 

 those in the older specimens invariably have only three (see figs. 49 and 50). These 

 facts incidentally bear out Mitsukuri's (14) statement with regard to the changes in 

 growth of spicules. 



The calcareous ring is simple, like that of a typical Aspidochirote. 



There are two long Polian vesicles in the specimen dissected. No stone canals are 

 seen. 



It is noteworthy that although this species has never been previously described, it 

 is evidently a fairly common form on the Ceylon coast. It is one of the species used 

 as " Trepang," and has apparently not been distinguished from some of the other 

 large species of Holothuria. Possibly, on account of its mottled appearance, it has 

 been confused with H. marmorata, from which, however, it differs in many respects. 

 The yellow transverse stripes (see Plate III., fig. 46) on the dorsal surface and the 

 mottling ou the ventral are very characteristic. 



Stichopus cliloronotus, Brandt. 



St. cylindricus, Haacke, 1880. See also Thkel (7). 



One specimen from East Cheval paar, 5^ fathoms. Length, 140 millims. 



This specimen agrees very closely with Theel's description. There are, however, 

 only 19 tentacles in the Ceylon specimen. 



There are four longitudinal series of protuberances on the dorsum, the two dorsal 

 series being double, while the two ventral series have a more or less zig-zag 

 arrangement. 



The pedicels are irregularly distributed over the ventral surface. Professor 

 LTerdman's notes state that the body was of a dark green colour when alive. 



Distribution : Pacific Islands, Indian Ocean from E. Africa to Malay Peninsula. 



Stichopus chloronotus, var. fuscus, nov. 



Three specimens from Pearl Banks, Gulf of Manaar (Stn. LVIIL), 9-2G fathoms. 

 Lengths, 170 millims., 200 millims., and 110 millims. 



