268 ' ENDEAVOUR " SCIENTIFIC RESULTS. 



part of the capsule they present a singular resemblance to the 

 old-fashioned ruff. A remarkable feature not hitherto noticed 

 is that instead of a series of annulations such as are generally 

 found in species of Sertularella, we have here a regular con- 

 tinuous spiral, making, when perfect, about seven or eight 

 complete turns round the gonotheca. The terminal part of 

 the topmost whorl rises quite abruptly at one side of the 

 tubular neck, which it almost equals in height ; it is here 

 nearly erect, but as it descends towards the middle part of the 

 gonotheca it spreads more outwards : towards the base it 

 becomes narrower and finally ceases. In a few cases, especi- 

 ally near the base of the gonotheca, the continuity of the 

 .spiral may become interrupted, and two or three complete 

 annulations may be found. 



Besides D. dichotomum several other species have been 

 referred to the genus Dictyodadium. As for D. flabellum, 

 Nutting, and D. reticulatum, Kirchenpauer, Levinsen has 

 .already pointed out that they belong to the genus Sertularetta, 

 as defined by him, and it will be apparent from the foregoing 

 description that D. dichotomum must keep them company. 

 But according to Hickson and Gravely the hydroid named by 

 them Dictyodadium fuscum (which Vanhoffen says is identical 

 with Selaginopsis affinis, Jaderholm), has no operculum, and 

 therefore cannot be associated with the three above men- 

 tioned. Whatever classification be adopted, I have at least 

 no hesitation in rejecting the genus Dictyodadium, which is 

 founded on no better ground than that of the colony forming 

 a flabellate structure, united into a network by the anasto- 

 moses of the branches. 



Locs. Off South Cape, Tasmania, 75 fathoms. 



Thirty-five miles south-east of Bruni Island, Tasmania, 

 150-230 fathoms. 



Genus SERTULARIA, Linne. 



Of the species here grouped provisionally under the old 

 genus Sertularia, S. minima and S. pusilla form, with their 

 allies S. minuta and S. muelleri, a distinct section characterised 

 by the possession of orifices in the hydrocaulus, generally 

 associated with tubular processes resembling minute sarco- 

 thecae. They are small unbranched forms, with the opercular 

 structure of Sertularia (Levinsen). 



S. loculosa is a member of the group of which S. marginata 

 {Kirchenpauer), better known as S. inflata (Versluys), is the 

 most familiar representative. This also belongs to Levinsen 's 

 Sertularia. 



