SPONGES. 323 



find their way to some suitable spot, where they develop 

 themselves into the parent form. 



Finally, here is a sort 1 whose colour is a pale Indian 

 red ; occurring in masses which take the form of thick, 

 plump bands, about half-an-inch in width, but alter- 

 nately swelling and contracting, which creep over the 

 rock, meeting and uniting, and then separating, so as to 

 leave hollow open interstices, which, however, in some 

 specimens are gradually filled up. The swellings form 

 pointed hillocks, the apices of which are pierced with 

 from one to three orifices. Irregular shallow channels 

 cover the hillocks, and converge to the apices. It 

 contains simple needles, slender, straight (or slightly 

 curved), pointed at each end, not very numerous, thickly 

 invested with granular flesh. This Sponge shrivels 

 much, and becomes shapeless in drying, but changes 

 little in colour. It is abundant. 2 



1 Microciona carnosa. 



2 I have been minute in the descriptions of these species, because the 

 student of marine zoology has so little to aid him in the identification of 

 our Sponges. This South Devon coast is peculiarly rich in these produc- 

 tions ; and several of these, though common here, are considered, as Dr. 

 Bowerbank tells me, quite rare. The figures, which I have drawn from 

 the life with great care, will, I trust, leave no difficulty in the identifi- 

 cation. 



Plate xxxvi. is devoted to the above species of Sponges. Beginning 

 from the upper right corner, we have Halichondria panicea, greenish yel- 

 low, with perforated hillocks : it occurs also in other parts of the picture. 

 The scarlet one next below is Grantia conacea. The black one to the 

 right is Halina Bucklandi. The plump buff one under the scarlet is Hali- 



