SPONGES. 13 



and the decay of the seaweed often leaves tubes of sponge 

 from a foot to eigliteen 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 Ray Society has been that followed in the 

 list. 



Suborder I. Calcaeea. 



Grantia comp-essa, Fabr. ; Bowerb. Brit. Sponges, 

 vol. ii. p. 17. 



Abundant on Cynthia 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 

 Rocks. 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 



