BRITISH SPONGIAD^. 11 



Type, Baphyrus Griffithsii, Bowerbank. Vol. I, Plate 

 XIII, Fig. 265. 



Suborder V. Compound reticulate skeletons, having the 

 primary reticulations tibro-spiculate, and the interstices 

 filled with a secondary spiculo-reticulate skeleton. 



DiPLODEMiA, Bowerbank. 



Skeleton fibrous. Fibres keratose, hetro-spiculous ; com- 

 bined with a secondary skeleton of ii-regular network 

 of spicula ; rete unispiculate, rarely bispiculate. Ova- 

 ries membranous and spiculous. Vol. I, p. 201. 



Type, Biplodemia vesicula, Bowerbank. Vol. I, Plate XIV, 

 Fig. 273 ; Plate XXXVI, Fig. 377 ; Plate XXIII, 

 Fig. 324. 



Suborder VI. Solid siliceo-fibrous skeletons. Skeletons 

 reticulate. Fibres composed of concentric layers of 

 solid silex, wdthout a central canal. Reticulations 

 unsymmetrical. 



Bactylocalyx, Stutchbury=j^A«Yeoi« of the Museum Jar- 

 din des Plantes, Paris. 



Dacttlocalyx. 



Skeleton siliceo-fibrous. Fibres solid, cyUndrical. Reticu- 

 lations unsymmetrical. Vol. I, p. 203. 



Type, Bactylocalyw pumicea, Stutchbury. Vol. I, Plate XV, 

 Figs. 274, 275, 276, and Plate XXV, Figs. 340, 341. 



