116 ir. M. Bale: 



tnuiRT-Turneretsclier, of Gruz, Austria; Professor ('. (' . Xuttiii^' 

 of Iowa City; Dr. C. McLean Fraser, of British Columbia; Pro 

 fessoi- S. F. Clarke, of VVilliamstown. Massachusetts; Dr. A. G 

 Mayei-, of Cambi'idge, Massachusetts; Dr. E. Warren, of Natal 

 Mr. Inal)a, of Kyoto; Mr. H. Farquhar, of Wellington; Mr. Thos 

 Whitelep:ge, of Sydney; Mr. J. F. Mulder, of Geelong ; Professor R 

 von liondenfehl. 



I have also to gratefully acknowledge the assistance rendered to 

 nif in other ways, especially by Professor Nutting. Dr. Stechow. 

 Dr. Hartlaub. Dr. Kirkpatrick, Mr. Ritchie, Dr. Billard and Mr. 

 Mulder, who have either sent me specimens, or compai-ed my speci- 

 mens with types, or otherwise assisted me in the endeavour to settle 

 the affinities of doubtful forms. 



Hydra vikidis Linne. 



Hydro I'ir/dis, Linne. Faun. Suec. 1746, p. ."'GT ; id., Syst. 

 Nat. L. 1767, p. 1320; Johnston. Brit. Zooph.. 1847. p. 

 121,%. 28; Hincks, Brit. Hydr. Zooph.. 1868, p. :n2. 

 fig. 40; Bedot, Zool. Anzeig. xxxix., 1912. p. 603. 

 Hydra riridissima, Pallas, Elenchus, 1766, p. .'il ; Brauer, 

 Zool. Anzeig, xxxiii., 1908. p. 790. 

 //. I'iridis lias not hitherto been included in lists of the Australian 

 hydi-oids. ]>ut it is found abundantly, in company with the brown 

 hydra, in ponds bordering the Yarra near Melbourne; and its 

 occurrence in those localities has been noticed in the " Victorian 

 Naturalist " on several occasions. 



Pknnaria wilsoni, n. noiii. 



Ifalocordyh aiisfralis. Bale, Proc. Roy. Soe. Victoria. N.S.. 

 vi.. 1893, p. 94. 



It is now generally recognised that the genus llaJdcortJ yle is not 

 really distinct fi-oni I'cniuirid , to which genus our //. oiistrali^ must 

 accordingly be relegated. In ordei- to avoid confusion with l'. aus- 

 Indis Bale (although that species is now considered by some 

 ol)servers to be only a variety of P. rarolinii), it seems advisable to 

 re-name the present form, which was dredged in Port Phillip by the 

 late Mr. J. Bracebi-idge WilsoTi. 



All the species hithei-to referred to /'rn/iaria api)ear to be iden- 

 tical in habit, the stem giving off two series of alternate branches, 

 which are both in the same plane, or nearly so, while the short poly- 

 l)iferous ramuli form a single series along the distal side of the 

 branches. In /-*. wilsoni (at least in the mounted specimens), the 



