HOLOTHURIOIDEA OF THE INDIAN OCEAN. 93 



branch of the respiratory tree is larger than the left. There 

 are Cuvierian organs present, in which character this species 

 agrees with Holothuria ocellqta. Cuvierian organs have not 

 yet been recorded in Holothuria spinifera. 



Spicules. — These consist of massive tables and knobbed 

 buttons. The buttons are the same as those of the other two 

 related species, but the tables are different. The tables are 

 characterized by having extremely high towers, each consisting 

 of four uprights and about eight cross-pieces. The tower is 

 surmounted by numerous teeth. Height of tower 125 [>-. 

 The disc of the tower is perforated irregularly by about 

 twenty or more holes and has a diameter of 120 [>-. The 

 supporting rods in the papillae are similar to those in Holothuria 

 ocellata. Holothuria martensii differs, therefore, from H. 

 ocellata and H. spinifera in the nature of the tables, in the 

 general integument, and from the latter species in having no 

 tables bearing large spines in the papillae. 



General Distribution. — East Indies, Ceylon, and Australia. 



Holothuria albiventer. Semper, 



(Plate XIV,, fig. 26.) 



Holothuria albiventer, Semper 1868 (38) ; Lampert 1885 (19), 

 1895 (21) ; Theel 1886 (42) ; Herouard 1893 (13) : 

 LudAvig 1899 (29) ; Sluiter 1901 (41) ; Pearson 1910 

 (34). 



Several specimens, collected by Professor Stanley Gardiner 

 in the Maldives. 



External Characters. — The ambulacral appendages consist of 

 papillae only, those on the dorsal side being small and numerous, 

 those on the ventral side being larger and less closely arranged. 

 In the spirit specimens at my disposal the bivium is clearly 

 marked from the trivium, not only by the disposition of the 

 papillae mentioned above, but also by the difference in colour. 

 The general colour is grayish-brown, but the trivium is 

 Ughter, especially on the papillae. In Semper's description 

 of the living animal he gives the colour as follows : — Bivium, 



