ICE Y 



TO THE 



AUSTRALIAN GENERA OF SPONQES 



DESCRIBED IN THIS CATALOGUE. 



I With skeleton composed of calcareous spi- 

 cules. (Calcarea.) 1 



<( With skeleton composed of siliceous spicules, 



horny fibre, or foreign bodies ; or without 

 I skeleton. (Silicea.) (2), p. 240. 



j' Without distinct chambers. (Asconidse.) . . 3 



1 < With sac-shaped chambers. (Syconidae.) . . (4) 

 \ With spherical chambers. (Leuconidae.) . . (5) 



3 With triactine spicules only Ascetta, p. 2. 



r Superficially projecting spicules, when present, 

 uniformly distributed over the surface. 



(4) y Spicules diact, triact, and tetract Sycandra, p. 3. 



Distant spines on the surface, composed of 



bunches of diacts. Sponge thin-walled . . Grantessa, p. 5. 



[ With triactine spicules only Leucetta, p. 6. 



(5) ) With triact and diact spicules Leucortis, p. 8. 



I With cUact, triact, and tetract spicules Leucandra, p. 9, 



' With triaxon, monact to hexact siliceous spi- 

 cules, slightly developed mesogloea, and 

 large sac-shaped or irregular chambers. 

 (Hexactinellida.) 



Without siliceous spicules ; with a skeleton 



