36 Mr. H. J. Carter on Specimens 



Ceratina. 



Aplysina purpurea^ n. sp. 



Form irregular, membranous, hollow, cactiform on the 

 surface. Colour black-purple. Fibre weakly developed, so 

 that, when elementarily examined, nothing can be distinguished 

 beyond a laminated condensation of the membranous structure 

 densely charged with purple pigment-cells like that of Ian- 

 lliellaflaoellrformis, Gray (ProaZool. Soc. Jan. 1869, p. 50), 

 extending among the Melobesian nodules and detritus of the 

 sea-bottom, so as to form an agglomeration in which the con- 

 trast of the dark pigment-cells and the purple stain that 

 accompanies them with the whiteness of the fragments over 

 which the sponge may be spreading is very striking, even to 

 the naked eye. In this respect it is very like A. naivus 

 (< Annals,' 1876, vol. xviii. p. 229, pi. xii. fig. 2). 



I also possess a large specimen of a similar sponge from 

 Trincomalee, on the N.E. coast of the island of Ceylon, in 

 which the purple colour is not so dark, but the fibrous struc- 

 ture is almost entirely absent, although the surface is cacti- 

 form and drawn up into puckered monticules ; so the latter is 

 not always dependent on the presence of fibre. It is pyra- 

 midal in shape, compressed, and 5 inches high, with a base 

 also 5 inches long and 2 inches thick. 



Aplysina fusca, n. sp. 



Massive, digitate, hollow, cactiform on the surface. Colour 

 dark brown. Growing like the last. Fibre well developed, 

 of a light brownish colour, opaque, hollow in its dry state, 

 with the axial cavity largely developed in proportion to its 

 horny investment. 



PSAMMONEMATA. 



Hircinia arundinacea, n. sp. (provisional). 



This imperfect specimen, which is in long stalks about 

 l-6th inch in diameter and of a light yellow colour, has had its 

 sarcodic parts replaced by the parasite which usually attacks 

 the Hircinice in all parts of the world, viz. Spongiophaga com- 

 munis. 



Hircinia fusca, n. sp. (provisional). 



Massive, digitate, branched lobate, cactiform on the surface. 

 Colour dark brown. Growing like the species of Aplysina 

 above described, but solid and charged with fibre covered with 

 foreign material. 



