Echinodermata, by Prof. F. J. Bell. 445 
Holothurta aspera. (Pl. XVIII. fig. 3.) 
Although there is but a single specimen of what I think is 
certainly a new species of Holothuria, the spicules appear to 
be so characteristic that there is no harm in giving a name 
to a form of which we shall, I hope, soon obtain a supply 
large enough to enable me to give a complete account of its 
special points. 
This single specimen is a good deal contracted and the 
tentacles are all withdrawn. ‘The skin has to the touch a 
peculiar roughness, which is no doubt due to the very dense 
deposit of spicules in it. Above, the skin is wrinkled, below 
it is smooth; on each side there is a single row of not closely 
packed pedicels ; no other processes. are to be detected. The 
colour of the skin is a dirty grey. The length of the body is 
77 millim. and the greatest breadth 46. 
The spicules are particularly difficult to isolate; their 
general form is well shown in fig. 8, Pl. XVIII. 
The processes or arms may touch or overlie one another. 
As there is only one specimen I have not dissected it. 
It was dredged at 1000 fath. 
EXPLANATION OF THE PLATES. 
PLatTE XVIII. 
Fig. 1. Phormosoma placenta laid open, so as to show the lantern and the 
parts adjacent thereto,. It will be noticed that the organs of 
Stewart are altogether wanting. Natural size. 
Fig. 2. The same, opened as before. s in three radii points to small pro- 
jecting ceca, two of which are quite small and the third hardly 
more than a papilla. Natural size. 
Fig. 8. Calcareous spicules from the skin of Holothuria aspera. X 220. 
PLATE XIX. 
Fig. 1. Echinus microstoma, The specimen from which this figure was 
taken agrees in all essential characters with one which is referred 
to the same species by the Rey. Dr. Norman and which was 
collecéed by the ‘ Porcupine.’ Natural size. 
Fig. 2. Echinus elegans, small specimen. X 2. 
Fig. 3. C-shaped spicule of Echinus elegans. X 220, 
Fig. 4. Astrogonium Greeni, seen from above. X §. 
