[Proc. Roy. Soc. Victoria, 27 (N.S.), Part I., 1914]. 



Art. Vll. — Further Notes on Australian Hydrolds. — ///. 



By W. M. bale, F.R.M.S. 



(With Plates, XI., XII., XIII.). 



[Read 9th July, 1914]. 



Orthopyxis, L. Agassiz. 



Campaniilaria, auct., in part. 



Ciytia, auct., in part. 



Laomedea, auct., in part. 



Eucopella, Von Lendenfeld. in part. 



Agasfra, Hartlaub. 



Trophosonie consisting of smooth or undvilated peduncles of vary- 

 ing length, springing from a creeping hydiorhiza, and supporting 

 each a single hydrotheca; hydrothecae campanulate. with the lower 

 part compressed, but usually circular above, the perisarc vaiying 

 much in thickness, but always greatly thickened inwards near the 

 base so as to form a " floor " on which the hydranth is supported; 

 hydranth radially symmetrical, with al)out 24-32 tentacles and a 

 large tiumpet-shaped hypostome. 



Gonothecae very variable in form within the limits of a species; 

 gonozooid a modified medusa^ having neither tentacles nor diges- 

 tivH cavity, l)ut provided with four branched radial canals, and 

 sometimes with marginal sense-organs. 



The sub-genus Orthopiixls, w^hich was proposed by Agassiz for 

 the reception of the single species Ciytia {Orthopyxis) poteritim (a 

 species Avhich had already been described by Hincks under the name 

 of Campminlaria c(dicidnta), has been disi-egarded by later ob- 

 servers, most of whom have been content to rank the species under 

 Ciytia or Campnnularia. 



In l.'^S.'? Von Lendenfeld desci-ibed as the type of a new genus 

 and family a species which he called Evcopella campanrdaria, and 

 which, he claimed, was distinguished from all previously known 

 hydroids by the possession of a gonozooid medusoid in character 

 but totally destitute of manubrium and tentacles. Aliliongh re- 

 ferring to Agassiz' work he failed to notice that the characters on 

 which he based his new genus were precisely those of the forii) 

 desci-ibed in great detail by the Ameriian luitiii alist. 



