216 
THE VOYAGE OF H.M.S. CHALLENGER. 
and several long Polian vesicles. The specimen obtained at Guadaloupe differs 
slightly, and forms a transition to Holothuria atm, to which both specimens 
bear a gTeat resemblance. The dorsal surface of this specimen is uniformly dark 
brown. The ventral surface is light yellowish-grey, with a broad longitudinal 
brown band along the odd ambulacrum ; ventral pedicels dark brown at the base. 
Anus with five minute groups of papillae. Among the dorsal slightly smaller 
pedicels, which, like the ventral ones, are destitute of supporting rods round the 
terminal plate, some appendages may be found which have a conical form and a 
small terminal plate surrounded by some rather strongly-formed supporting rods. 
Holothuria edulis, Lesson, 1830; Semper, 1868. Trejpang edulis, Jaeger, 1833. Holo- 
thuria fusco-cinerea, Selenka, 1867. 
Dorsal papillae minute, and more scattered than the ventral pedicels. The disks of 
the tables reduced to a small ring, narrower than the top of the spire, which, 
seen from above, presents a small circular hole surrounded by four prominences, 
each with about four or five minute teeth. The fenestrated plates nearly like 
those in Holothuria grisea. 
Habitat. — Philippine Islands (Semper, Lesson), Mozambique (Semper), Molucca Islands 
(Lesson), Amboina (Selenka, Ludwig), New Holland and Caroline Islands 
(Lesson), Aden (Semper), Celebes (Selenka, Ludwig), Java and Timor (Ludwig). 
(Mus. Holm.) One specimen, 250 mm. long, from the Fiji Islands, and a smaller one 
from New Britain. Colour — dark reddish-brown on the back, light greyish on 
the ventral surface and the sides ; a minute dark ring round the base of the 
light pedicels. The dorsal papillae are very minute. A single Polian vesicle. 
A small bundle of about four minute, free, madreporic canals on each side of the 
dorsal mesentery. The base of the tables always narrower than the top. The 
small fenestrated plates often incomplete, resembling x -shaped spicules. The 
species is doubtless nearly allied to Holothuria atra, but seems to be well defined 
by the colour, the shape of the tables, &c. 
4. In addition to tables with a small annular disk, finely granulated 'perforated 
plates 'with the holes arranged in t'wo longitudinal series. 
Holothuria unicolor, Selenka, 1867. 
The ventral pedicels much more numerous than the dorsal. Tables like those in 
Holothuria atra and Holothuria mexicana. The plates are finely granulated, 
slightly irregularly formed, with smooth margins and numerous holes arranged 
in two series, each series composed of about two irregular rows. 
Habitat. — Barbados (Selenka). 
Semper refers this species to the group, which is characterised by papillae on the dorsal 
surface. It bears the nearest resemblance to Holothuria raexicana or Holothuria 
atra. 
