AUSTRALIAN HYDROMEDUS/E. 4-5 



II. Sub-familia HYDRACTININ^E. V. Lendenfekl, 18S4. 

 Sexual generation. Medusostyles. 



63. Genus DEHITELLA. Gray (?). 



Hydrophyton dichotomous, perisarc dark-brown. Perisarc of spiral zooids 

 vertical on the stem and branches (?) Differs from Ceratella by the equal 

 distribution of the tufts of spicules. Spiralzooids 1 



225. Delritella atrorub3iis. Gray. (9) 49, (19) 47, (95) 612. 

 East coast of Australia (Bondi Bay). 



64. Genus CERATELLA. Gray (?). 



Hydrophyton irregularly dichotomous. Perisarc dark-brown. Hydranths, 

 polypostyles, and medusoid buds unknown. The detail description of the 

 skeleton by Gray is worthless. 



226. Ceratella fusca. Gray. (9) 48, (19) (47) (95) 612. 

 Australia. 



III. SUB-ORDO.-HYDROCORALLIN^E. 



Moseley, 1876. 



Alimentary zooids, with few verticillate, capitate tentacles. Hydrorhi/.a 

 forming a dense calcareous skeleton, which also invests the polyps. Groups 

 of niachopolyps, in the form of tentacular zooids, surround the alimentary 

 polyps. Ultimately generative zooids are probably medusa 1 . (2) (111). 



XIY. Familia STROMATOPORID.E. 



Murie and Nicholson, 1878. 

 Possessing undulating lamina? in the skeleton. 



XV. Familia MILLEPORIM]. 



Moseley, 1877. 



Alimentary zooids, with four to six tentacles. Polypary with many conic 

 spaces, divided by tabula?. Ccenenehym, with reticulating canals. Daetylo- 

 zooids, with numerous tentacles. Ampulla? absent. 



65. Genus MILLEPORA. Moseley. 



In the centre of each irregular group of dactvlozooids one alimentarv polyp. 

 110. 



227. Millepora tortuosa. Dana. (27) 545, (95) 613. 

 Fiji Islands. 



