762 SOME NEW AND RARE HYDROIDA IN THE AUSTRALIAN MUSEUM, 



Gonothecae large, obovate, strongly annulated, (10-12 rings), 

 orifice rather wide, infundibulate, mostly excentric. 



Hah. — Bondi Bay. 



This form might with almost equal propriety be assigned either 

 to S. divaricata or to the southern Australian *S'. Johnstoni (if 

 indeed it be not, as appears likely, one of a series of transition 

 forms uniting the two). In the bushy haV)it and the compara- 

 tively short internodes it rather i-esembles <S'. Johnstoni, but its 

 hydroth3C8e are more like those of S. divaricata, being adnata 

 most of their length, and only slightly projf^cting forward. The 

 peristome often consists of several successive growths. The gono- 

 thecae are a little smaller than those of the type, with closer and 

 more numerous rings ; the aperture is precisely similar. The 

 polypary is much shorter and more bushy than that of the variety 

 sub-dichotoma,, but the pinnae or ramuli, as in that form, are given 

 off at irregular intervals, so that the pinnate habit is lost. 



Sertularella loxgitheca, n.sp. 

 (Plate XVI., figs. 5 6). 



Hydrocaulus slightly branched, divided by oblique joints into 

 internodes which bear one or occasionally two hydrothecao. 

 Hydrothecae adnate from ^ to h of their length, long, narrow, 

 tubular, smooth, curved outwards, springing from the sides of the 

 liydrocaulus or | tartly from the fiont ; aperture not contracted, 

 with three large teeth, one superior and two lateral. 



Gonothecse rather large, without annulations, somewhat widened 

 laterally, with a shoulder at each side of the aperture ; aperture 

 small, tubular, not expanding. 



Hab. — Port Denison. 



The only specimen I have seen was 2^^ inches high, and consisted 

 of a monosiphonic stem with five or six simple lateral branches. 

 The hydro thecae are toothed like those of the -S". Jo/mstoni group, but 

 are nearly double as loug in proportion to their diameter, while 



