EEPORT ON THE HOLOTHURIOIDEA. . 181 
buttons (PI. YIL fig. 10, d) have generally six boles, but it is not very rare to find them 
with eight holes, especially in the papillse. 
The third specimen, obtained at the Fiji Islands, is like that from the Philippine 
Islands in colour and general appearance. 
Holothuria atra, Jseger, 1833 (PI. YIL fig. 4); 
Habitat. — Amboina ; a single individual. Fiji Islands ; a single specimen. 
Station 177, August 18, 1874; lat. 16° 45' S., long. 168° 7' E.; depth, 130 fathoms; 
bottom, volcanic sand ; a single specimen. 
Each of the specimens obtained at the above mentioned Stations has a length of 
about 180 mm.; when fully extended they must be much longer. The dorsal papillm are 
much more scattered than the ventral pedicels, and do not exceed them in size. Some of 
the tentacles seem to be absent in the specimen from Amboina. The deposits have been 
already correctly described by Selenka. The small disks of the tables (PL VII. fig. 4, a) 
are either smooth on the margin or provided with spines. Close to the well-developed 
terminal plate of the pedicels, fenestrated, often symmetrically bilateral plates are to be 
found. The papOlse, on the contrary, contain slightly curved, smooth, or spinous rods, 
mostly with the enlarged ends fenestrated or branched. The colour is darkish brown, 
almost black. The Polian vesicles often seem to be more than three in number. The 
terminal plates of the dorsal papillae are very rudimentary. 
Holothuria ciiriosa, Ludwig (PL VIII. fig. 9).- 
Hahitat . — Samboangan (Philippine Islands). 
The only specimen brought home by the Challenger Expedition almost completely 
agrees with that described by Ludwig. Its length is about 100 mm., and its colour is 
greenish-brown, darker on the dorsal surface, and almost black round the anal aperture. 
A fine distinct darkish brown ring surrounds the bases of the pedicels and papillae. 
The pedicels are slightly more crowded than the papillae. The very small, irregularly 
but closely placed dorsal papillae seem to be situated on small warts. The slightly 
larger ventral pedicels are also scattered without order. The anus is round, and the 
mouth surrounded by a slight brim. 
The calcareous ring is of the usual shape without posterior prolongations. LTnlike 
the animals examined by Ludwig, the Challenger specimen is furnished with only a 
single vesicle, 25 mm. long. 
The single, free, dorsal madreporic canal has a length of 6 to 7 mm. The 
reproductive organs are very small, and their fine, narrow tubes are once or tvdee 
