Report on the Hydroids. 369 



with similar angles to those above-mentioned, but the space between 

 the planes of the side-branches here looks backwards, the terminal 

 hydrotheca is bent forwards and so on. — There are not a few di- 

 vergences from this rule, however; not seldom there is only one 

 side-branch, more seldom three. The branches are mostly smooth ; 

 at their distal part there are hourglass-shaped constrictions. All the 

 branches are of about the same thickness, ca. 110^, their length is 

 somewhat variable, on an average ca. 1.2 mm. — The pedicels of 

 the secondary hydrothecae are of dill'erent length, at the base con- 

 sisting of one or more hourglass-shaped nodes or with more irreg- 

 ular constrictions, sometimes only with a single ring-shaped con- 

 striction; the distal part is smooth. The hydrothecae are short, the 

 rim very much everted and bent backwards; ca. 20 chitinous warts; 

 the average distance of these from the uppermost part of the aper- 

 ture (the distance a in text-figure 8) is 34«, i. e. 



ca. Vn of the diameter of the rim. Nearly as - — \ I... ... ■I"' 



far (on an average 32 дг) under the chitinous 

 warts there is always a well-developed pseu- 

 dodiaphragm in the form of a closed ring, 

 equally developed on all sides. The diameter 

 of the free rim of the aperture is on an average 

 164^, that of the proximal part of the hydro- 

 theca (at the chitinous warts) ca. 106/^. — The - " 'ь- 

 chitin has a light brownish colour. The hydranths are very badly 

 preserved. 



Gonothecae are not present. 



The species described here has some resemblance to Jäderholm's 

 figure of Haleciiim tenellum Hincks (1909 (27), Taf. IV, fig. 12). Yet 

 I can scarcely believe that the specimens belong to H. tenellum. 

 Against such a \ie^\ is the constant possession of a pseudodiapliragm, 

 the shortness of the hydrotheca, the rather great thickness of the 

 branches and the stalks in proportion to the diameter of the rims 

 of the hydrothecae, and the characteristic habit of the entangled 

 branches spread out in all directions. Unfortunately I have no nor- 

 thern material of H. tenellum at my disposal, otherwise measure- 

 ments would most likely be able to decide the question, if it is a 

 variety of H. tenellum or an independent species, for which I would 

 then propose the name Halecium lex tum. 



Of this species there is a by no means small material from St. 

 96, in part growing on Sertnlarella gigantea. 



Hab.: St. 96. 



Depth: 160—180 m. 



