CLASSIFICATION. 
Spong . 9 
3. Psammopemma , Marshall. Without differentiated skeletal 
fibres; skeleton afforded by foreign enclosures lying 
separately in the parenchyma, horny substance confined 
to a thin envelope around the enclosed foreign bodies. 
Fam. Spongidce. 
1. Coscinoderma , Carter. Skeletal fibres admitting of no dis¬ 
tinction into primary and secondary ones. 
2. Euspongia, Bronn. With fine skeletal fibres, forming a com¬ 
pact network, the meshes being very small; primary and 
secondary fibres readily distinguishable. 
3. llippospongia , F. E. Schulze. With fine skeletal fibres and 
small meshes, the fibres admitting of no distinction into 
primary and secondary ones ; distinguished by a system of 
canals permeating the body in all possible directions. 
4. Cacospongia, 0. Schmidt. With readily distinguishable pri¬ 
mary and secondary skeletal fibres of comparatively thick 
diameter and forming comparatively large meshes. 
5. Stelospongus , O. Schimdt. With comparatively thick skeletal 
fibres united in separated columns, directed more or less 
regularly, radiating from the basis of the sponge towards 
the outer surface, and consisting each of a compact net¬ 
work of vertical primary and horizontal secondary fibres. 
6. Carteriospongia , Hyatt. Form flabellate, leaf-like, or funnel- 
shaped ; skeletal fibres distinguishable into larger primary 
and smaller secondary ones ; flagellated chambers devoid of 
any inhalent and exhalent canaliculi ; -with ribbed outer 
surface. 
Fam. Aplysinidce. 
1. Luff aria, 0. Schmidt. With thick-w 7 alled heterogenous 
skeletal fibres, their central part but little differentiated 
optically from the surrounding horny lamina. 
2. Verongia , Bowerbank. The central axis of the thick-walled 
skeletal fibres readily distinguishable optically from the 
surrounding horny walls. 
Lendenfeld (19) commences a classification of the Horny Sponges as 
follows :— 
Order. Ceraospongi^e, Bronn. Sponges with a skeleton composed of 
horny fibre ; siliceous (flesh) spicules, produced by the sponge 
itself, may occur in the mesoderm, but never in the horny 
fibres. 
Suborder 1. Microcamer^e. With small spherical flagellated cham¬ 
bers. 
Fam. 1. Spongidce , F. E. S. Flagellated chambers small, hemi¬ 
spherical to spherical, communicating with inhalent 
lacunae by numerous pores, with exhalent canals and 
lacunae by wide pores or canals; fibres forming a 
network ; axis of fibres very thin ; main fibres often 
containing foreign bodies ; ground mass about the 
chambers containing granules. 
