THE STRUCTURE OF ALCYONIDIUM GELATINOSUM. 33 
EXPLANATION OF PLATE III. 
Fig. 1. Young Alcyonidium gelatinosum on shell, showing 
elongated pear shape. 
Fig. 2. Calcareous spicules found in peripheral parts. 
Fig. 3. Longitudinal section of a cell as seen in a trans- 
verse section of A. gelatinosum. 
a, Ctenostome; 6, tentacular sheath; c, ten- 
tacles; d, lophophore; e, cells surrounding the 
mouth end of the tentacular sheath; /, funiculus; 
g, stomach; hf, hairs surrounding mouth, some 
on short papille; 7, intestine; &, anal opening; 
mf, rouscular fibres. 
N.B.—Only such parts are shown as have a 
bearing on the paper. 
Fig. 4. The tentacular sheath as seen from below:—d and 
mf, as in fig. 3. 
