HYDROIDA. BALE. 323 



Locs. Great Australian Bight, Long. 126 45J' E.', 190-320 

 fathoms. 



Great Australian Bight, Long. 130 40' E., 160 fathoms. 

 Great Australian Bight, Long. 127 20' E., 180 fathoms. 

 Eastern Slope, Bass Strait, 80-300 fathoms. 



AGLAOPHENIA (THECOCARPUS) CALYCIFERA, Bale. 



Aglaophenia calycifera, Bale, Biological Results " Endea- 

 vour," ii., 4, 1914, p. 178, pi. xxxvii., figs. 3-4. 



The nodes of the hydrocladia are described as "transverse" ; 

 a more correct description, in the great majority of cases, 

 would be " slightly oblique." 



Locs. Great Australian Bight, Long. 126 45^' E., 190-320 

 fathoms. 



Great Australian Bight, Long. 130 40' E., 160 fathoms. 



AGLAOPHENIA (THECOCARPUS) MEGALOCARPA, Bale. 



Aglaophenia megalocarpa, Bale, Biological Results " En- 

 deavour," ii., 1, 1914, p. 45, pi. iv., fig. 1, pi. vi., fig. 5. 



The peculiar positions of the hydropore and the intra- 

 thecal ridge, along with the form of the lateral sarcothecse, 

 to which I have referred as so exceptional, are exactly 

 paralleled in some of the forms which Billard, in his " Report 

 on the Siboga Plumulariidse," has ranked as varieties of 

 Thecocarpus myriophyllum. From all those forms the hydro - 

 thecse of A. megalocarpa differ in the denticulation of the 

 border, and in the crest on the median tooth. 



Loc. Great Australian Bight, 80-120 fathoms. 



Genus HALICORNARIA, Busk. 



Of the species of Halicornaria comprised in the collection 

 H . superba and H. furcata var. intermedia belong to the ascidi- 

 cndes-group, distinguished by the position of the abcauline 

 intrathecal ridge ; H. urceolifera and var. scandens belong to 

 the longirostris-group, in which the intrathecal ridge is 

 wanting ; H. vegce and H. tubulifera form a group, new to 

 the Australian region, having no intrathecal ridge, and dis- 

 tinguished by the peculiar and characteristic ramification, 

 which moreover is polysiphonic ; and H. birostrata is distinct 

 from all the others in the position of the intrathecal ridge, 

 in the forked anterior sarcothecse, and in other particulars. 



