96 PORIFERA. 



Sub-fam. 1. Renierinae. Spicules may be enveloped by a small pro- 

 portion of spongin, but are never completely enveloped in it. Halicliondria 

 Fleming, littoral ; Petrosia Vos. ; Renicra Nardo ; Calyx Vos. 



Sub-fam. 2. Chalininae. Spongin plentiful ; spicules enveloped and 

 united by it. Pachycludina Schni. ; Chalina Grant ; SipJionochalina 0. 

 Schm. ; Cacoclialyna 0. S. ; Chalinorrliaphis Lend. ; Hoplochalina Lend. 

 Fam. 2. Heterorraphidae. Megascleres of various forms ; microscleres com- 

 monly present, but never chelre. 



Sub-fam. 1. Phlceodictyinae. Sponge massive, with tubular processes 

 (fistulfe) projecting from it. With a well-marked external rind. Megasclera 

 oxea, passing into strongyla in some species. Rhizoclialina Schmidt ; 

 Oceanapia Norman. 



Sub-fam. 2. Gelliinae. Megascleres all diactinal, oxea, or strongyla. 

 Microsclera as sigmata or toxa ; no rind or fistulas. Gc Hius Gray ; Gelliodcs 

 Ridley ; Toxochufimt Ridley. 



Sub-fam. 3. Tedaniinae. Megascleres of two forms monactinal (styli) 

 forming the main skeleton, diactinal (tylota or tornota) dermal. Micro- 

 sclera as rhaphides. Tcdania Gray ; Trachytcdania Ridley. 



Sub-fam. 4. Desmacellinae. Megascleres all monactinal, stylote to 

 tylostylote. Microscleres sigmata or toxa, or both. Desmacella Schm.; 

 Eicmma Gray. 



Sub-fam. 5. Hamacanthinae. Megascleres oxea or styli. Microscleres 

 large diancistra, and sometimes others. Vomcrula Schm. ; Hamncantha 

 Gray. 



Fam. 3. Desmacidonidae. Megascleres of various forms, usually monactiual. 

 Microscleres always present and always including chelre. 



Sub-fam. 1. Esperellinae. Skeleton fibre not echinated by laterally 

 projecting spicules. Espcrclla Yos. ; Espcriopsis Carter ; Cladorhiza M. Sars, 

 megascleres long, often projecting radially, like spines, deep-sea ; Axoniderma 

 R. and D. ; Chondrocladia W. Thomson, deep-sea ; Mcliidcrma R. and D. ; 

 Desmacidon Bow. ; Artemisina Vos. ; Phclloderma R. and D. ; Sideroderma 

 R. and D. ; lophon Gray; Amphilectus Yos.; Dcndoryx Gray; Forcepia 

 Carter ; Yvcsia Topsent ; Metonanchora Carter ; Damiria Keller, etc. 



Sub-fam. 2. Ectyoninae. Skeleton filjre echinated by laterally projecting 

 spicules. Myrilla Schmidt ; Pytheus TOJIS. ; Clathria Schm. : Rhaphidophlus 

 Ehlers ; Stylostichon Tops. ; Microciona Bow. ; Uymcraphia Bow. ; Plocamia 

 O.S. ; Plumohalichondria Carter; Acarnus Gray; Ecliinoclathria Carter; 

 Agelas Duch. and Mich. ; Echinodicttjum Ridley. 



Fam. 4. Axinellidas. Skeleton typically non-reticulate, consisting of ascend- 

 ing axes of fibres from which arise subsidiary fibres radiating to the cortex. 

 Megasclera chiefly styli, to which oxea or strongyla may be added. Microsclera 

 rarely present, never chelate. Hymcniacidon Bow. ; PhakcUia Bow. ; Ciocalypta 

 Bow. ; Acanthella Schm., Axinclla Schm., generally branched ; Rnspdilia Nardo, 

 branched, whip-like; Dendroims R. and D. ; Thrinacophora Ridley; Dictyo- 

 cylindrus Bow. 



Fam. 5. Spongillidae. Fresh-water sponges. Asexual reproduction by 

 gemmules which are often surrounded by a special kind of spicules called 

 amphidiscs. Spongilla Lamarck; Epliydatia Lamouroux ; Tubella Carter; 

 Parmula Carter ; Hctcromeycnia Potts ; Lubomirskia Dybowski ; Lesscpsia 

 Keller ; Uruguaya Carter ; Potamolepis Marshall. 



