THE HYDROMEDUSAE 55 



Allm. [?]. FAMILY 10. PLUMULARIIDAE (gonophores probably sessile 

 throughout). Genera Plumularia, Laink. pars.; Antennularia, 

 Lamk. ; Acanthella, Allm. ; Schizotricha, Allm. ; Sciurella, Allm. ; 

 Polyplumaria, G. 0. Sars ; Heteroplon, Allm. ; Nemertesia. FAMILY 11. 

 CALICARPIDAE. Genera Calicarpa [?] ; Hippurella, Allm. [?]. FAMILY 1 2. 

 HYDROCERATINIDAE. Genus Clathrozoon, Spencer [?]. INCERTAE SEDIS 

 Trichydra, S. Wright [?] ; Coppinia, Hassall [?]. 



ORDER 3. Trachomedusae. (For definition, see p. 30.) 



FAMILY 1. PETASIDAK Genera Petasus, Hkl. ; Lipetasus, Hkl. ; 

 Petasata, Hkl. ; Petachnum, Hkl. ; Aglauropsis, F. Mull. ; Gossea, L. Agass. ; 

 Olindias, F. Miill. FAMILY 2. TRACHYNEMIDAE. Genera Trachynema, 

 Gegenb. ; Marmanema, Hkl. ; Rhopalonema, Gegenb. ; Pectyllis, Hkl. ; 

 Pectis, Hkl. ; Pectanthis, HkL ; Homoeonema, Maas. ; (?) Pantachogon, Maas. 

 FAMILY 3. AGLAURIDAE. Genera Aglantha, Hkl. ; Aglaura, Pe"r. Les. ; 

 Agliscra, Hkl. ; Ktauraglaura, Hkl. ; Persa, M'Crady. FAMILY 4. GERY- 

 ONIDAE. Genera Liriantha, Hkl., = Liriope, Less. ; Glossoconus, Hkl. ; 

 Glossocodon, Hkl. ; Geryones, Hkl. ; Geryonia, P4r. Lea ; Carmaris, Hkl. ; 

 Carmarina, Hkl. 



ORDER 4. Narcomedusae. (For definition, see p. 33.) 



FAMILY 1. CUNANTHIDAE. Genera Cunantha, Hkl. ; Cunarcha, Hkl. ; 

 Cunoctantha, Hkl. ; Cunoctona, Hkl. ; Cunina, Esch. ; Cunissa, Hkl. 

 FAMILY 2. PEGANTHIDAE. Genera Polycolpa, Hkl. ; Polyxmia, Esch. ; 

 Pegasia, P^r. Les. ; Pegantha, Hkl. FAMILY 3. AEGINIDAE. Genera 

 Aegina, Esch. ; Aeginella, Hkl. ; Aegineta, Gegenb. ; Aeginopsis, Brandt ; 

 Aeginura, HkL ; Aeginodiscus, Hkl. ; Aeginodorus, Hkl. ; Aeginorhodus, 

 Hkl. FAMILY 4. SOLMARIDAE. Genera Solmissus, Hkl.; Solmundus, 

 HkL ; Solmundella, Hkl. ; 'Solmoneta, Hkl. ; Solmaris, Hkl. 



ORDER 5. Hydrocorallinae. (For definition, see p. 35.) 



FAMILY 1. MILLEPORIDAE. Genus Millepora, Linn. FAMILY 2. 

 STYLASTERIDAE. Genera Sporadopora, Moseley; Pliobothrus, Pourtal. ; 

 Erritia, Gray ; Distichopora, Lamk. ; Labiopora, Moseley ; Spinipora, 

 Moseley ; Allopora, Ehrenb. ; Stylaster, Gray ; Stenohelia, S. Kent ; 

 Conopora, Moseley ; Cryptohelia, M. E. and H. ; Astylus, Moseley. 



ORDER 6. Siphonophora. (For definition, see p. 38.) 

 SUB-ORDER 1. DISCONECTAE. 



Definition. Siphonophora with an apical chambered pneumatophore, 

 without nectophores or bracts. The individuals are confined to the lower 

 surface of the pneumatophore, and are a single central gastrozooid, 

 surrounded by concentric girdles of blastostyles and dactylozooids. 



FAMILY 1. DISCALIDAE. Genera Discalia, Hkl. ; Disconalia, Hkl. 



