50 HOLOTHURIOIDEA. 
Body elongated, flattened behind, with the podia almost entirely 
confined to the ventral surface. Integument very soft, body-wall 
rather thick, deposits scarce. Dorsal surface papillose. The 
deposits are perforated with four large holes. 
Colour—sometimes dark above, with yellow tentacles and lower 
surface, but it may be of “ all shades, from sienna to rose-colour and 
delicate pink.” 
Remarkable for the large size of the Cuvierian organs, some of 
the tubes of which may often be seen protruding from the anus ; 
or a packet ready for expulsion may be seen in the cloaca. These 
tubes are very extensile, and have great sticking powers. 
Distribution. Not certainly known except in the British area; 
common off West Irish coasts. 
a. Cleggan Bay, 4-9 fms. Royal Dublin Society. 
6. Donegal Bay, 30 fms. Royal Dublin Society. 
c. Kenmare River. 
d-t. Durgan, near Falmouth. J. Snell, Esq. 
j, k. Polperro, 20 fms. 
4, Coast of Cornwall, G. F. Tregelles, Esq. 
m-—o. Coast of Cornwall. 
p. Plymouth. 
4, Holothuria aspera. 
Holothuria aspera, Bell, Ann. § Mag. iv. (1889) p. 445, pl. xviil. 
fig. 3 
Spicules of Holothuria aspera. X 220. 
This species is only known from a single specimen, which is re- 
markable for its spicules; they have, typically, a central cavity and 
six projecting spokes. They are densely deposited in the skin, which 
is peculiarly rough. Above the skin is wrinkled, below it is smooth; 
on each side there is a single row of not closely packed podia. 
Colour dirty grey. Length 77, greatest breadth 46 mm. 
a. S.W. coast of Ireland, 1000 fms. (‘Type.) ‘Flying Fox’ Exp. 
