1867.] DR. J. n. GRAY ON SPONGES. 



51/i 



fibres, with single or groups of spicules radiating from its outer sur- 

 face. Spicules uniform, fusiform or needle-shaped. 

 Ophistospongia, Bowerb. B. S. ii. p. 378. 



Ophistospongia australis. 



Australian sponge, Bowerb. B. S. i. p. 275, t. 17. f. 28S. 



See also — 



Ophistospongia papilla, Bowerb. B. S. ii. p. 37H. 



Hab. Guernsey. 



2. Seriatula. 

 Sponge massive. Skeleton of solid, cylindrical, horny, thick and^ 

 slender fibres, with small imbedded spicules. Spicules smooth, of 

 three forms — (1) broad needle-shaped, (2) pin-shaped, and (3) fusi- 

 form, slender, angularly bent. 



Seriatula seriata. 



Spongia seriata, Grant. 



Chalina seriata, Bowerb. B. S. ii. p. 376, f. 287 (outer surface) ; 

 O. Schmidt, Supp. ii. t. \C)7 ■ 



3. Ectyon. 



Sponge massive, reticulated, of cylindrical horny fibres, with single 

 scattered or groups of diverging spicules. Spicules fusiform, verti- 

 cillated, spined. 



1. Ectyon sparsus. 



West-India sponge, Bowerb. B. S. i. p. 27^, t. 17- f. 289. 

 Spicules scattered, or in pairs or threes. 

 Hab. West Indies. 



2. Ectyon fascicularis. 



West-India sponge, Bowerb. B. S. i. p. 276, t. 17. f. 2!)(t. 

 Spicules grouped together in fascicules. 

 Hab. West Indies. 



3. Ectyon carpenteri. 



Halichondrial, Carpenter, Microscope, p. 538, f. 267. 



Hab. Madagascar. 



See Biplodemia, Bowerb. B. S. f. 377; but it has armed orisacs. 



4. ACARNIA. 



Sponge parasitic, membranaceous, with erect and recumbent cla- 

 vate spinose spicules. Spicules subcylindrical or subclavate ; ends 

 blunt, covered with spines. 



AcARNIA CLIFTON I. 



Hymeniacidon cliftoni, Bowerb. B. S. i. p. 276, f. 7<>, 'So, 2!)1. 

 Hab. Freemantle, West Australia (G. Clifton). 



