Inclusion of Foreign Bodies by Sponges. 395 



mounted in the ]3ritish Guiana Museum vvliicli I examined 

 some years ago, and noted the characters of its nose-pad. 

 This siiull closely agrees with tlie dimensions of F. Cuvier's 

 type kindly supplied to me by Prof. Trouessart. 



In addition we have a skin without skull from Trinidad, 

 therefore a to[)otype of F. Cuvier's L. insularis, which it may 

 be taken to represent. 



Unfortunately, as Prof. Trouessart informs me, the typical 

 mounted skins of neither L. enudris nor L. insularis are now 

 to be found in the Paris Museum. Happily by the help of 

 the type skull of the former and the British Museum topotype 

 of the latter we are able to identify both with practical 

 certainty. 



LXIV. — The Inclusion of Foreign Bodies hy Sponges, with a 

 Description of a new Genus and Species of Monaxonida. 

 By Igerna B. J. yOLLAS. 



Owing to the kindness of the captain of the ' Durham Castle ' 

 the Members of the British Association were allowed to land 

 at Mozambique and at Mombasa on the homeward journey 

 from South Africa in September 1905. An opportunity of 

 half an hour's shore-collecting was thus afforded, and at 

 Mozambique there was a ricli growth of sponges, particularly 

 of Cinachyra voeltzkowi, Lfd. Oue sponge, Miyas porphyrion, 

 gen. et sp. n., which, owing to its consistency and general 

 appearance, 1 sup[)Osed would prove to be a member of the 

 Ceratosa, is, in fact, an interesting form of Monaxonida 

 which possesses a skeleton consisting of both ''proper'^ spicules 

 and foreign bodies. Certain features in the cortex of this 

 specimen seem to me to throw some light on the method by 

 which foreign bodies are included in this case and possibly 

 also in the case of other sponges. 



Migas porphyrion is a massive sponge ; the surface is 

 raised into a system of low ridges. The single specimen 

 which 1 possess measures 4'5 x 2"a cm. A tine individual 

 of Cinachyra voeUzkoioi has lixcd and grown upon a part of 

 its surface. The colour when living was dark purple, out- 

 wardly butf in the deeper parts ; in spirit the purple has 

 turned to grey. The dark pigment is contained in the 

 granular cells of the cortex. The cortex is '8 mm. at its 

 greatest thickness and contains large cavities. The chambers 

 are very small, "015 mm. in tlianieter, few and aphodal. 



