Dr. J. E. Gray on the Classification of Sponges. 461 



with a depressed central cavity ; lower part of the body with 

 numerous scattered anchorate rooting spicules. 



Lophurella^ = Tetilla loplmra^ O. Schmidt, tab. 



Dactylella^ = Tethya dactyloidea. Carter, Ann. & Mag. N. H. 

 1869, vol. iii. p. 15. 



*** Sponge free ; hose surrounded hy a funnel-shaped expan- 

 sion or dish formed of elongated spicules united together. 



Fam. 7. Casuladae. 



Casula = Tethya casula, Carter, Ann. & Mag. Nat. Hist. 

 1871, vol. viii. p. 99, pi. 4. 



B. Sp)onge without elongate tricurvate spicules^ with stellate 

 groups of spicules in the outer surface and inner part of 

 the sarcode. 



Fam. 8. ChondrilladaB. 



1. Stellate spicules of one kind. Chondrilla. 



2. Stellate spicules of distinct kinds. Corticium, 



III. Sponge without glohidar halls of spicules or stars ^ hut with 

 elongate spicules^ two- or three-rayed and recurved at the 

 outer end, on the margin of the sponge. 



Fam. 9. Ancorinidae. 

 Ancorina^ Normania. 



Section B. POTAMOSPONGIA. (Freshwater Sponges.) 



Sponge freshwater, of a green colour ; ova coriaceous, 

 strengthened with variously shaped spicules jjlaced in the 

 substance of the ovisacs ,* they are found in the substance of 

 the massive branched sponge, which is strengthened by fusi- 

 form spicules ; sponge spiculose, with fusiform spicules in a 

 sarcode. 



Fam. 1. Spongilladae, Proc. Zool. Soc. 1867, p. 550. 



1. The spheres thick, smooth, armed with birotulate spi- 

 cales. Ephydatia^ Dosilia. 



2. Spheres tessellated on the surface, and with sunken fusi- 

 form spicules. Afetania, Acalle, Drulia. 



3. Spheres covered externally with fusiform spicules. Eu~ 

 napius and Spongilla. 



