SPONGES. 93 



of these bodies and their taxonomic value are extremely doubtful. Sollas (15) 

 mentions that such bodies occur in the Tetillkke associated with sigmaspires, 

 hut in Oinachyrcc barbata, where they are said to be as much as 0"0535 millim. in 

 diameter, he regards them as " accessory or accidental " forms, and the only species 

 of Tetilla in which they are mentioned appears to be Tetilla arabica (Carter), where 

 they are of about the same size as in T. anomala. I myself have seen similar bodies 

 in one specimen of Tetilla hirsuta (ride swpra), but only very locally developed. 

 That the spherules are really siliceous appears to be tolerably certain, for they 

 appear abundantly in preparations of T. anomala which have been boiled out with 

 nitric acid. Whether they can be regarded as definite and characteristic spicules is, 

 however, another question, and it appears to me not impossible that they may be 

 simply reserves of siliceous material destined to be re-absorbed later on and used 

 for spicule formation. This view is strongly supported by their very sporadic 

 distribution. 



There is possibly a close relationship between T. hirsuta, T. poculifera, and 

 T. anomala. 



R.N. 153 (Station V., off Chilaw, 10 fathoms) ; 192 (Station LVIL, outside Dutch 

 Modragam Paar, 11^ to 3(5 fathoms). 



Tetilla limicola, n. sp. Plate I., fig. 7 ; Plate III., fig. 6. 



Sponge (Plate I., fig. 7) somewhat fig-shaped, constricted below, broadly rounded 

 above ; may be slightly lobose ; may be laterally compressed ; anchored in the mud 

 by a great mass of fine silky spicules attached to the base. Surface glabrous, but 

 at the same time minutely and sparsely hispid above, more strongly hispid on the 

 sides ; also very minutely reticulate on the upper parts. Texture soft and spongy, 

 but very compact, i.e., without wide canals or cavities in the interior. Colour in 

 life, pink ; in spirit, grey. Vents (Plate I., fig. 7, o) of fair size, several, slit-like, 

 in deep or shallow depressions on the upper part of the sponge ; each leading into 

 a wide but shallow cloaca! cavity with an almost flat floor perforated by numerous 

 minute openings of very narrow exhalant canals. Inhalant pores scattered between 

 the surface tufts of spicules. A spirit specimen (exclusive of the root tuft) measures 

 about 43 millims. in height, 48 millims. in greatest breadth, and 31 millims. in 

 greatest thickness. The root-tuft (Plate I., fig. 7, r.t.) is nearly as large as the 

 specimen itself, and in its present condition consists of a mass of soft mud held 

 together by the extremely long and slender silky anchoring spicules, which 

 individually are scarcely visible to the naked eye. 



The skeleton consists of the following parts : 



(1.) Loose longitudinal bands of very long, slender oxea run almost parallel to one 

 another throughout the body of the sponge. In a longitudinal section taken across 

 the greatest breadth of the sponge these fibres are seen to converge towards a point 

 situated at a short distance below the depressed apex of the sponge. Owing to the 



