102 OKHAMANDAL MARINE ZOOLOGY REPORT— PART II 



Register Number, Locality, &c. XXVI. 13, Adatra Eeef, 25 December '05. 



8. Chondrilla agglutinans, n. sp.— (Plate I., Figs, la, ih.) 



The sponge occurs as a sort of matrix, holding together and partially enveloping 

 a mass of Siliquaria and other shell-fragments, together with sand and pebbles. The 

 surface is glabrous and approximately smooth except where wrinkled by contraction 

 in spirit. The colour in spirit is chocolate-brown of varying shades. Oscula small, 

 in irregular groups, their margins flush with the general surface. 



The cortex is barely 0-1 mm. thick, and is covered by a very distinct cuticle. Even 

 in stained parafiin sections I have been unable to detect the inhalant cortical canals, 

 so conspicuous in the closely related C. mixta [Schulze 1877]. It is distinctly fibrous and 

 also contains numerous pigment-cells filled with minute brown granules. Its outer 

 half is densely packed with spherasters arranged in several layers. 



The colour of the sponge appears to be due chiefly to the presence in the choanosome 

 of numerous spherical cells of a brown colour, scattered singly and in dense groups. 

 Each of these brown cells is about 0-01 mm. in diameter. Their colour may, however, 

 possibly be due to staining by colouring matter extracted by alcohol from the pigment- 

 cells. They remind one of the fat-like bodies described by Schulze [1877] as possible 

 reserve-material in Chondrosia reniformis, and of the similar bodies described by Carter 

 [1887 his] in his Chondrosia spurca, and of the bodies regarded as possible symbiotic algae 

 by myself [1905] in Hexadella indica, &c. 



There are two kinds of aster present, closely resembling those of Chondrilla mixta, 

 viz. spherasters and oxyasters. The former (Fig. la) occur chiefly in the outer part of 

 the cortex, but also sparingly in the inner part of the cortex, and still more sparingly 

 in the choanosome. They have a very large centrum and numerous smooth, sharp, 

 conical rays touching each other at their bases ; the total diameter is about 0-028 mm. 

 The oxyasters (Fig. 1&) appear to be confined to the choanosome, where they are very 

 sparingly scattered. They have a small or indistinguishable centrum, and comparatively 

 few, rather slender, smooth, sharp-pointed, conical rays, say about eight or ten in 

 number. The total diameter of this spicule is about 0-02 mm. 



Register Number, Locality, <&c. V. 1, S. of Chindi Reef, 6-10 fms., 18.12.05. 



9. Tetilla dactyloidea (Carter).— (Plate II., Figs. lOa-lOc.) 

 Tethya dactyloidea Carter [1869]. 

 Tethya dactyloidea Carter [1872]. 

 Tethya dactyloidea Carter [1887]. 

 Tetilla dactyloidea Sollas [1888]. 

 Tetilla dactyloidea Keller [1891]. 

 Tetilla dactyloidea var. lingua Annandale [1915]. 



