1886.] POSITION AND CLASSIFICATION OF SPONGES. 587 



2. Subfamilia Ectyonince, Ridley and Dendy. 



Fibre echinated by laterally projecting spicules. 



Myxilla, Schmidt ; Clathria, Schmidt ; Rhaphidophlus, Ehlers ; 

 Plumohalichondria, Carter ; Acarnus, Gray ; Echinoclathria, Carter ; 

 Clathrissa, Lendenfeld ; Thalassodendron, Lendenfeld ; Cerao- 

 spina, Lendenfeld. 



5. Familia Axinellid^, auct. 



With large subdermal cavities. Skeleton non-reticulate, consist- 

 ing of ascending axes of fibre, from which arise subsidiary fibres 

 radiating to the surface pervading the subdermal cavity. Fibres 

 plumose. Megasclera chiefly styli, to which oxea and strongyla 

 may be added. Microsclera rarely present, never chelae. 



Dendropsis, Ridley and Dendy; Thrinaeophora, Ridley; Hyme- 

 niacidon, Bowerbank ; Phakellia, Bowerbank ; Ciocalypta, Bower- 

 bank ; Acanthella, Schmidt ; Axinella, Schmidt ; Baspailia, Nardo ; 

 Spirophora, Lendenfeld. 



II. Suborder Keratosa, Bowerbank, emend. 

 Silicea with a supporting skeleton composed of spongin ; fibre 

 with or without foreign bodies, but always without proper spicules. 

 Flesh-spicules may be present. Exceptionally, there is no skeleton 

 at all. 



i. Tribus MicrocamercB, Lendenfeld. 



With small spherical ciliated chambers and opaque ground- 

 substance. 



1. Familia Spongid^, F. E. Schulze. 



With narrow axial thread in the horny fibres, and without fila- 

 ments. 



1. Subfamilia Aulenince, Lendenfeld. 

 Reticulate sponges with vestibules, without flesh-spicules. 

 Halme, Aphroditella, Halmopsis, and Aulena, Lendenfeld ; Psam- 

 maclema, Marshall. 



2. Subfamilia Chalinopsillinee, Lendenfeld. 



When dry of light yellow colour, digitate, lamellar, more or less 

 flower-shaped, imitating very closely ChaHainte, from which they 

 appear only recently to have developed. Without flesh-spicules, 

 with smooth surface. 



Ghalinopsilla and Antheroplax, Lendenfeld j Daetylia, Carter. 



3. Subfamilia SpongincB, Lendenfeld. 



Massive, when dry dark brown, with conulated or granulated 

 surface. Vestibules, when present, belong^exclusively to the inhalant 

 system. Without flesh-spicules. 



Eusponpia, Bronn ; Cacospongia, Schmidt ; Hippospongia, F. E. 



