THE AUSTRALIAN HYDROMEDUS^. 



By R. von Lendenfeld, Ph.D. 



Part V. — Conclusion. — Plates XX. to XXIX. 



THE HYDROMEDUSIN^E, HYDROCORALLIN^E AND 

 TRACHYMEDUS^E. 



II. SUBORDER HYDROMEDUSIN^E. 



Von Lendenfeld, 1884. 



COLONIES OF POLYMORPHIC ZOOIDS. THE ALIMENTARY 

 ZOOIDS RETAIN THE SHAPE OF POLYPES, WHILST THOSE IN 

 WHICH THE SEXUAL PRODUCTS REACH MATURITY ARE 

 MEDUSAE, WHICH MAY BECOME FREE OR REMAIN ATTACHED 

 TO THE COLONY AND BECOME RUDIMENTARY. 



9. FAMILY ANTHOMEDUSIDyE. Yon Lendenfeld, 1884. 



ANTHOMEDUS^E. Haeckel, without the Cytaeida; of Haeckel. 



Medusa? become free, without Otoliths, with Ocelli at the base 

 of the tentacles. Gonads in the outer or oral wall of the gastral 

 cavity. Mostly four Radial Canals. The Polyp colonies on which 

 these Medusae bud, contain alimentary Zooids, which are not 

 invested by chitinous cups. The Medusa? bud mostly on the 

 ordinary alimentary Polyps, exceptionally they are also born on 

 peduncles and bud direct from the Hydrorhiza. A division of 

 labour between alimentary Polyps and Polyps which produce 

 Medusa? ; Polypostyles do not occur. 



