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DEPARTMENT OF THE NAVAL SERYICE 

 Family HEBELLID^. 



Trophosome. Oolony simple, creeping; hydranths with conical or dome-shaped 

 proboscis; hydrothecae tubular, diaphragm present, no operculum. 

 Gonosome. Gonangia separate, not collected in a mass. 



Genus Hebella. 



Trophosome. A creeping stem gives rise to single hydranths, attached by short 

 pedicels; diaphragm present in the hydrothecse. 



Gonosome. Gonophores producing free medusae. 



KF.Y TO SPECIES. 



a Hydrotheca tubular, pedicel very short. 



h Hydrotheca urceolate, pedicel longer, annulated. 



H. calcarata. 

 *H. po&illum. 



Hehella calcarata {A. Agassiz). 



Trophosome. Colony creeping over hydroids or 

 occasionally the stem may be free for a short distance; 

 hydrotheeae tubular, coming off singly or in pairs from 

 the stolon, almost sessile. 



Gonosome. Gonangia large, oblong - obovate, 

 smooth, almost sessile; aperture terminal, small. 



No. 68. 



Hebella calcarata. 



Hehella poclllum. (Hincks). 



Trophosome. Stem creeping, hydrotheca' urceolate, on 

 relatively long, annulated pedicels. 



Gonosome. Unknovpn. 



Family LAFCFID.E. 



Xo. 09. 

 Hibilla pdciUiDii. 



Trophosome. Hydrotheeae tubular; margin entire; no operculum; hydranth with 

 conical probosciis; no diaphragm in any of the genera here included. 

 Gonosome. Gonangia closely crowded to form a coppinia mass. 



KEV TO GEXERA. 



a Hydrotheeae directly attached to a reticular stolon. Filcllum. 



h Hydrotheeae attached to a fascicled stem. 



c Hydrotheeae free or very slightly adherent. Lafcea. 



cc Hydrotheeae partly immersed in the main portion of the stem but not 

 distally. Cri/ptolnrin. 



ccc Hydrotheeae partly immersed in the stem throughout its whole length. 



Grammaria: 



