BRITISH Sl'ONGIAD^. 49 



As I received at tlie same tiaie a specimen of Tethea lyn- 

 curium, and the type specimen oiSpongia pulchella, Johnston, 

 described in the ' British Miscellany,' it is very probable 

 that Mr. Sowerby had it from the man to vi^hom he alludes, 

 and that its locality was probably either Shetland or the 

 Orkney Islands. It has the form of rather less than half 

 of a depressed turnip. The section is two and three quarter 

 inches in length and one and a half in height, and from 

 the fiat section to the furthest part of the opposite curve it 

 measures one inch*. It agrees completely in its organic 

 characters with the type specimen. 



When Dr. Fleming favoured me by sending to me the 

 type specimen of his Cydonium Mulleri, he sent with it 

 two other specimens ; one of them is labelled, " From the 

 Island of Dominica, in the West Indies," and proved to be 

 Geodia gibherosa, of Lamarck ; the other was labelled, 

 " From the Cape of Good Hope." In this specimen I have 

 been unable to discover such organic difference as to entitle 

 it to be considered distinct from G. Zetlandica. It is 

 two and a half inches long, two inches broad, and one iach 

 in height. The dermal membrane is entirely destroyed by 

 washing or maceration, and nearly all the sarcode is removed 

 from the sarcodous membranes by the same cause. There 

 are hirsute spicula very closely set and numerous on some 

 parts of the depressions on the surface, protruding nearly 

 the eighth of an inch, and in other parts of the sponge, 

 where none of them appear above the surface, their remains 

 are equally abundant when a section at right angles to the 

 surface of the sponge is observed by the microscope, and it 

 is therefore evident that at one period of its existence it was 

 hirsute on all of its external parts. 



At the bottom of two deep, funnel-shaped depressions on 

 the sponge, completely obscured by the great hirsute spicula, 

 there appeared to be single oscula ; these orifices were 

 about the size of the large ones in Dr. Fleming's specimen 

 of C. Mulleri {Geodia Zetlandica), but I could not detect 

 smaller ones, 'either single or in groups, on any part of its 

 surface, in consequence of the uncertainty induced by the 

 total destruction of the dermal membranes. Some parts of 



