107 HYDROIDA. BALE. 



it usually bends a little upward again, so that the distal half is 

 not horizontal but slightly ascending ; there are, however, here 

 and there exceptions, whei'e the direction may vary. The free 

 portion is of nearly equal diameter throughout. The rim may 

 have a number of renewals close together, or they may be more 

 distant, commencing in some of the hydrothecae nearly as far 

 back as the middle of the free portion. 



The structure of the stem is not so dense as to preclude the 

 course of the hydrothecse being easily traced through the 

 enveloping tubes, except in the thickest portions of the hydro- 

 caulus, 



Loc. Great Australian Bight, 100 fathoms. 



FAMILY SERTULARIID^E. 

 Genus HYPOPYXIS, All man. 

 HYPOPYXIS DISTANS, sp. nov. 

 (Plate xxxv., figs. 2-5.) 



Stems monosiphonic, thick, seven or eight inches or more in 

 height, giving off a number of irregular branches on one or both 

 sides, which are separated from the long slender cladophores by 

 very long oblique joints ; nodes on both stem and branches at 

 distant and irregular intervals. 



Hydrothecae arranged alike 011 stem and branches, in rather 

 distant pail's, opposite and in contact in front, very widely 

 separated behind, large, erect, adnate nearly their whole length, 

 somewhat contracted towards the aperture, which is vertical ; 

 margin thin, membranous, with two very slight angular lateral 

 lobes ; operculum abcauline ; a pouch-like appendage in front 

 and at the side, near the base. " Stalk-marks " conspicuous. 



Gonothecae very large, elongate-ovate, smooth, summit 

 narrowing in to the small circular elevated border ; a number of 

 irregular processes projecting into the interior for some distance 

 below the rim. 



Colour. Brown. 



This hydroid exhibits a close affinity with the II. labrosa 

 of the " Challenger " Report, and may possibly have to be united 

 to it when more is known of the relations of the two forms, in 

 which case the name distan-s may stand as a variety-name, 

 indicating the most patent distinction between them. The 

 interspaces between consecutive pairs of hydrothecas on the 



