758 SOME NEW AND RARE HYDROIDA IN THE AUSTRALIAN MUSEUM, 



Campanularia marginata, Bale. 



Bondi ; Coogee (plentiful), (Mr. T. Whitelegge). 



I have mentioned in the " Catalogue " that some of the hydro- 

 thecge of this species have the remains of an operculum visible, 

 but in these specimens the structure alluded to is not present. 

 It is a very delicate membrane, and in the few cases where I have 

 met with it was incomplete. It may probably be a temporary 

 structure like that which covers the immature hydrothecse of 

 various species of Obelia. 



LAFOETD^. 



Lafoea scandens, n.sp. 



(Plate XIIL, figs. 16-19). 



Hydrophyton parasitic on other hydroids ; hydrorhiza slender ; 

 hydrothecse springing directly fi'om the hydrorhiza, tubular, 

 straight or slightly curved, rounded below to the level of the 

 " floor," basal portion short, contracted, pedicle very short ; 

 aperture simple, margin very slightly everted, often double or 

 triple. 



Gonangia about double the length and diameter of the hydro- 

 thecse, tapering downwards in the lower half ; with more or less 

 distinct transverse undulations ; margin with three or four shallow 

 emarginations ; summit of the blastostyle forming a trumpet- 

 shaped expansion ; gonophores two, both on the same side of the 

 blastostyle. 



Hah. — Port Stephens; Port Jackson; mostly on Sertularella 

 divaricata, var. sub-dichotoma. 



The specimens of Sertidarella divaricata from Port Stephens 

 were quite overrun by this species, its hydrothecse in some paits 

 equalling or even exceeding in number those of the Sertularella. 

 So far as I am aware, it is the first species of Lafoea in whicli 

 the gonosome has been observed. The gonothecse were fairly 



