SPONGES. 
13 
and the decay of the seaweed often leaves tubes of sponge 
from a foot to eighteen inches in length. In like manner the 
greatly increased size of Grantia ciliata , the vast abundance 
of Hymeniacidon celata, its beautiful arborescent patterns 
in the tide-worn shells, and its perforations in the limestone 
rocks are diagnostic of the warmer waters of the southern 
coast. 
The classification of Dr. Bowerbank in his valuable work 
published by the Bay Society has been that followed in the 
list. 
Suborder I. Calcarea. 
Grantia compressa , Fabr.; Bowerb. Brit. Sponges, 
vol. ii. p. 17. 
Abundant on Gyntliia grossularia under shelving rocks 
between tide-marks, and attached to the roots of Fuci and 
other seaweeds. It occasionally assumes an abnormal form, 
and has a broad attached surface under stones. Longest, 
3 inches. 
Grantia ciliata , Fabr. ; Bowerb. vol. ii. p. 19. 
Not unfrequent on laminarian roots cast on the West Sands 
after storms, and growing near low-water mark at the East 
Bocks. The species somewhat resembles a grain of oat re¬ 
moved from its husk. 
Leucosolenia hotryoides , Ellis & Sol.; Bowerb. vol. ii. p. 28. 
Abundant on the under surfaces of stones in tidal pools, 
especially if large and little-disturbed. It frequently accom¬ 
panies Grantia compressa. 
Leuconia nivea , Grant; Bowerb. vol. ii. p. 36. 
Found abundantly in the deeper tidal pools, under large 
