152 SPONGES 



jEphydatia, Lamx. ( = Meyenia, Crtr.) ; Heteromeyenia, Potts ; Tubella, 

 Crtr. ; P&rmula, Crtr. ; Carterius, Potts ; Uruguaya, Crtr. ; Potamolepis, 

 Marshall ; Lessepsia, Keller. SUB-FAMILY (d). GELLIODLNAE, Tops. 

 Skeleton formed of long thick spicular fibres, with very little spongin 

 as a rule ; but in Phoriospongia and Sigmatella the spicules of the 

 fibres are replaced by foreign bodies (arenaceous fibres) and the spongin is 

 abundant. Microsclere usually sigmata. Genera Gelliodes, R. ; Slylo- 

 trichophora, D. ; Cladocroce, Tops. ; Phoriospongia, Marshall ; Chon- 

 dropsis [Crtr.], D. ( = Sigmatella^ Ldf.). SUB-FAMILY (). PHLOEODIC- 

 TYINAE, Crtr. Massive sponges with a thick cortex and fistula? ap- 

 pendages. Framework of choanosome, a network of spicular fibres. 

 Microscleres, when present, sigmata. Genera Rhizochalina, O.S. ; 

 Oceanapia, Tops. FAMILY 2. IPOECILOSCLERIDAE, Tops. ( = DESMA- 

 CIDOIUDAE, R. and D. + HETERORHAPHIDAE, R. and D., pars.). Megas- 

 cleres almost always monactinal ; microscleres various, but almost always 

 including chelae. SUB-FAMILY (a). JESPERELLINAE, R. and D. Skeletal 

 fibres without echinating spicules ; megascleres of ectosome similar to 

 those of choanosome, or differing only in size. Genera ^Esperetta, Vosm. 

 ( = Esperia, Ndo.), [Eoc.] ; Gomphosteyia, Tops. ; 7 Esperiopsis, Crtr. [Eoc.], 

 (Fig. 37) ; j Amphilectus, Vosm. [Eoc.] ; Stylotella, Ldf. ; Desmacella, 

 O.S. ; Biemma, Gray ; Monanchora, Crtr. ; jHamacantha, Gray (= Vome- 

 rula, O.S.), [Eoc.] ; Pozziella, Tops. ; jdadorhiza, M. Sars [Eoc.] ; jChon- 

 drocladia, W. Th. [Eoc.] ; Axoniderma, R. and D. ; Meliiderma, R. and D. ; 

 Artemisina, Vosm. ; Phelloderma, R. and D. ; jDesmacidon, Bwk. [Eoc.] ; 

 Batzella, Tops. ; Homaeodictya, Ehlers ; jGuitarra, Crtr. ; [Eoc.] ; Sidero- 

 derma, R. and D. ; Joyeuxia, Tops. ; Microtylotella, D. ; Amphiastrella, 

 D. SUB- FAMILY (6). IDENDORICINAE, Tops. Skeletal fibres without 

 echinating spicules. Megascleres of ectosome, as a rule, different from 

 those of choanosome, and usually diactinal. Genera Dendoryx, Gray ; 

 Lissodendoryx, Tops. ; ^loplion, Gray [Eoc.] ; lotrochota, R. ; Leptosia, 

 Tops. ; Tedania, Gray ; Trachytedania, R. ; ^Forcepia, Crtr. [Eoc.] ; 

 jMelonanchora, Crtr. [Eoc.] ; Histoderma, Crtr. ; Cornulum, Crtr. ; 

 Yvesia, Tops. SUB-FAMILY (c). fECTYOKIHAB, Crtr. Skeletal fibres with 

 echinating spicules, which are usually spined. Genera jMyxilla, O.S. 

 [Eoc.] ; Pocillon, Tops. ; Phimohalichondria, Crtr. ; Sttjlostichon, Tops. ; 

 Microciona, Bwk. ; Hymeraphia, Bwk. ; Tylosigma, Tops. ; Acheliderma 

 Tops. ; jAcarmis, Gray [Eoc.] ; Pytheas, Tops. ; Hamigera, Gray ; 

 Spanioplon, Tops. ; Clathria, O.S. ; Echinoclathria, Crtr. ; Agelas, Duch. 

 et Mich. ; Ophlitaspongia, Bwk. (Fig. 32) ; Ectyonopsis, Crtr. ; Rhaphi- 

 dophlus, Ehlere ; Echinonema, Crtr. ; Clathriodendron, Ldf. ; Plectispa, Ldf. ; 

 Clathriopsamma, I/if. ; Aulena, Ldf. ; Echinodictyum, R. ; Kalykenteron, 

 Ldf. ; Fusifer, D. SUB -FAMILY (d). IBUBARINAE,. Tops. AVith special 

 diactinal spicules, localised at the surface of attachment or forming the 

 axis- of the sponge ; or with special megascleres (rhabdostyles). Genera 

 jPlocamia, O.S. ( = Dirrhopalum, R.), [Cret. Eoc.] ; Suberotelites, O.S. ; 

 Bubaris, Gray ; Cerbaris, Tops. ; Bhabderemia, Tops. ; Hymerhabdia, Tops. 

 FAMILY 3. f AXINELLIDAE, R. and D. Megascleres typically monactinal ; 

 diactinal spicules, when present, usually of subsidiary importance in 

 building up the skeletal framework. Microscleres wanting or few in 



