INTRODUCTION. 



Family XII. Pennariidae. 

 VORTICLAVA, Alder. | ACHARADRIA, Wright. 



Suborder IL THECAPHORA. 



Hydroida furnished with thecse. 



Family I. Campanulariidse. 



CLYTIA, Lamouroux. 

 OBELIA, Per. & Lesueur. 

 CAMPANULARIA, Lamk. 



LOVENELLA, HillclvS. 



THAUMANTIAS, Escli. 

 GONOTHYR.EA, Allman. 



Family II. CampanuliiiidaB. 



CAMPANULINA, Van Ben. 

 ZYGODACTYLA^ Brandt. 



OPERCULARELLA, Hincks. 



Family III. Leptoscyphidse. 

 LEPTOSCYPHUS, Allman. 



Family IV. Lafoeidae. 



LAFOEA, Lamouroux. 

 CALYCELLA, Hincks. 

 CUSPIDELLA, Hincks. 



SALACIA, Lamouroux. 

 FILELLUM, Hincks. 



Family Y. Trichydridae. 

 TRICIIYDKA, Wright. 



Family VI. Coppiniidse. 

 COPPINIA, Hassall. 



Family VII. Haleciidse. 

 HALECIUM, Okcn. OI'HJODES ; Hincks. 



