TRANSACTIONS OF MICROSCOPICAL SOCIETY. 
DESCRIPTION OF PLATE VII, 
Illustrating Dr. Bowerbank^s paper on the Organization of 
Grantia ciliata. 
Fig. 
1. — Grantia ciliata, natural size, having the mouth of the cloaca open. 
2. — Grantia ciliata, natural size, having the mouth of the cloaca completely 
closed. 
3. — Six of the intestinal cells from the front of a longitudinal section of 
the sponge mounted in Canada balsam, showing the mode in which 
the terminal cones of spicula fall on one side in a state of repose. 
a. One of the cells in the condition of active inhalation. 
b. A cell, having the terminal spicula in a partially closed condition. 
4. — A portion of the large ciliary fringe of spicula from the mouth of the 
cloaca of the sponge, in the closed condition ; showing the mode of 
the disposition of the rectangular, triradiate, and spiculated rect- 
angular spicula, near the base of the long, slender, acerate spicula 
forming the ciliary cone for the defence of the mouth of the cloaca. 
5. — Spicula of Grantia ciliata. 
a. Equiangular triradiate spiculum of the skeleton. 
b. Acerate spiculum from the defensive cone of the inhalent system. 
c. A portion of a long, attenuated, acerate spiculum from the defensive 
ciliary fringe of the mouth of the cloaca. 
d. One of the large fusiformi-acerate spicula supporting the base of the 
ciliary fringe of the mouth of the cloaca. 
e. A rectangular triradiate spiculum from near the base of the ciliary 
fringe of the mouth of the cloaca. 
/. A spiculated, rectangular, triradiate, defensive spiculum from the 
base of the ciliary fringe of the mouth of the cloaca. 
g. A spiculated, equiangular, triradiate, defensive spiculum from the 
interior surface of the cloaca. 
