226 
THE VOYAGE OF H.M.S. CHALLENGER. 
Holothuria insignis, Ludwig, 1875. 
Habitat. — Bowen, Hong Kong, and Red Sea (Ludwig). 
Even this form resembles the three preceding very strikingly, and probably they 
are all varieties of the same species, and nearly related to Holothuria pardalis. 
Holothuria inhahilis, Selenka, 1867. 
Pedicels all over the body. The solid tables have twelve spines on the margin of the 
disk. The very numerous buttons are of a more unusual shape, symmetrical, 
swollen, with two rows of “ minute ” holes, about four holes in each row ; the 
surfaces of the buttons are uneven owing to the presence of flattened elevations 
(no knobs), and their margin is deeply undulated. 
Habitat . — Sandwich Islands and Society Islands (Selenka). 
Holothuria rugosa, Ludwig, 1875. 
Ventral surface with numerous pedicels ; dorsal surface with scattered papillae. The 
tables consist of a large spinous disk and a long conical spire which is usually 
composed of six rods, and carries four to six long and strong teeth on the top. 
The buttons have six to seven pairs of holes. 
Habitat . — Navigator Islands and Waygeeoo (Ludwig). 
(Mus. Hohn.) One specimen, 160 mm. long, from Pelew Islands, and two from New 
Britain. Colour, yellowish-white. The tables have the characteristic form 
mentioned by Ludwig, but the conical spire seems mostly to be composed of 
only four rods, though I found tables with even six rods and with more 
teeth. The buttons are fewer in number than the closely placed tables, and 
among those with numerous holes I even found buttons with only six holes. 
Papillae and pedicels supported by transformed tables and numerous bilaterally 
symmetrical, perforated plates ; the former with very rudimentary terminal 
plates, the latter with well-developed ones. 
y. Disks of the tables spinous or smooth on the margin. Number of tentacles from 
twenty-five to thirty. 
Holothuria discrepans, Semper, 1868. 
Ventral surface with numerous pedicels; dorsal surface with thinly scattered papiUae. 
The rounded disk of the tables with undulated smooth margin, seldom provided 
with a few spines, and having commonly some of the peripheral holes confluent 
with the central one. Spire terminating in several teeth (about twelve). 
Buttons of more symmetrical and usual shape, with about six holes, present 
only near the pedicels. Tentacles thirty. 
