584 DR. R. VON LENDENFELD ON THE SysTeMaTIC [Dec. 21, 
2. Familia SoLLASELLID#&, Lendenfeld. 
Digitate forms with radiating spicule-bundles, and distinct ecto- 
and endochone. 
Sollasella, Lendenfeld. 
3. Familia SprrastRELLID#, Ridley and Dendy. 
With spirastrellid flesh-spicules. 
Spirastrella, Ridley ; Raphyrus, Bowerbank ; Papillina, Schmidt; 
~ Cheirella, Lendenfeld ; Awos, Gray ; and Coletrar. ona, Lendenfeld. 
Coincides with the family Gheirciides Lendenfeld. 
4. Familia SUBERAMATIDA, nov. 
With hamate flesh-spicules (sigmata). 
Suberamata, Lendenfeld. 
5. Familia SuBeRITIDZ, Vosmaer, emend. 
Without flesh-spicules. 
Suberitella, Lendenfeld ; Suberites, Nardo ; Suberopetros, Lenden- 
feld ; Plectodendron, Lendenfeld ; Polymastia, Bowerbank ; T'richo- 
stemma, M. Sars; Tentortum, Vosmaer (Thecaphora, O. Schmidt) ; 
Stylocordyle, Wyv. Thomson ; Quasillina, Norman; Cliona, 
Grant; and Poterion, Schlegel. 
Iv. Subordo OL1GosiLicina, Lendenfeld. 
Without supporting skeleton. Flesh-spicules, when present, 
anaxon polyactinellid. Chambers small, with narrow outlet. 
1. Familia CoonpRILLID&, Lendenfeld. 
With polyactinellid flesh-spicules. Comprises the genus Chon- 
drilla, O. Schmidt. 
2. Familia CoonpRosip#, Lendenfeld. 
Without flesh-spicules. Comprises the genus Chondrosia, Nardo. 
III. Ordo CORNACUSPONGIA, Vosmaer, emend. 
Silicea with soft mesogloea, or mesodermal ground-substance. 
The supporting skeleton is composed of bundles of monaxonids, 
which are never tylostyle spicules. The skeleton is strengthened 
by spongin, which cements the spicules. These may disappear 
altogether, and the skeleton is then composed of spongin, with 
or without foreign bodies. Exceptionally, also, this horny skeleton 
disappears. The ciliated chambers have large outlets. 
1. Subordo HALICHONDRIN‘A, Vosmaer. 
With siliceous spicules in the supporting skeleton. 
1. Familia SPonGILLIDA, Carter. 
Freshwater sponges with gemmule. 
Spongilla, Lamarck ; Ephydatia, Lamouroux; Tubella, Carter ; 
