ACT1N1ARIA 



Exp. kerguelensis) 4857'8 S. 7Oo6' E., 88 m (German Tiefsee-Exp. 1898). 

 South Georgian 5422' S. 36a8' W. Kocktopf bay 22 m, clay and algae (Sw. 

 South Polar-Exp. 1902, N. 33), 54!!' S. 36i8' W. Cumberland bay 252 

 310 m, gray clay with stones. Temperature at the bottom 1,45 (Sw. South 

 Polar-Exp. 1902 N. 34), Graham region about 643' S. 563;' W. 360 m? 

 Clay. (Sw. South Polar-Exp. 1902, St. 6). 



Exterior aspect: The body is either cylindrical or oval, according to the state of contraction. 

 Very expanded specimens reach a considerable length, and also in very contracted specimens the length is 

 much larger than the breadth. The column, secerning a mucus-membrane, shows no distinct division in re- 

 gions. The proximal part is rounded, physa-shaped and perforated by apertures which are, at least in larger 

 specimens, 24 in number and arranged in two cycles. No central pore is present, which was also stated by 

 Appellof (1896) of the specimens collected by Danielssen. Studer declares that purpurea is furnished 

 with only one aboral pore, an opinion which is adopted by Kwietniewski. This is, however, not the case, 

 as I have been able to prove on the type-specimen. The aboral "pore" is nothing but a lowering, caused by 

 the contraction of the proximal body-end. When the ectoderm is pencilled away here, it is distinctly seen 

 that no central pore is present in the middle of the proximal end, the presence of such a pore is besides 

 impossible, because of the coalescence of the mesenteries in the centre. On the other hand, I have, in several 

 compartments, found 2 radially placed pores. It admits of no doubt that purpurea resembles abyssorum and 

 clavus, as regards the arrangement of the pores. The column is furnished with mostly distinct longitudinal 

 furrows corresponding to the insertions of the mesenteries, and lacks each trace of papillae; its ectoderm 

 forms no cuticle. The tentacles of the adult specimens, which are short in proportion to the length of the 

 body, are 12 in number, cylindrical, sometimes pointed, according to the state of contraction, and all of the 

 same size. In a small specimen from Cumberland bay, 0,7 mm long and 0,2 mm broad, without reproductive 

 organs, the number of tentacles was only 8. The tentacles all may be invaginated, so that the ectoderm is 

 turned inwards, thus we may find now one or two, now almost all or all the tentacles invaginated. In the 

 latter case the animal seems to be without tentacles, and on the margin of the oral disc only crateriform 

 openings, surrounded by walls, are to be observed. The tentacles sometimes show shallow longitudinal fur- 

 rows, sometimes a deeper furrow appears on the middle of the tentacles also observed by Appellof. 

 In H. clavus Hertwig has seen a longitudinal furrow both on the inside and the outside. Any greater im- 

 portance in systematic respect I cannot ascribe to these furrows, as they are most probably due to an irre- 

 gular contraction of the tentacles. The oral disc is broad and radially sulcated. The siphonoglyphes are not 

 distinctly differentiated from the outer part of the actinopharynx and lack gonidial-tubercles and aboral 

 prolongations. The actinopharynx is short, of about the length of the tentacles and provided with 12 high 

 longitudinal ridges, extending directly into the middle streak of the filaments. On the actinopharynx of 

 the preserved specimens numerous transversal folds are also to be observed. 



Anatomical description: The ectoderm of the column is high with numerous gland-cells. The 

 nematocysts are of two different kinds here, in the actinopharynx of three kinds, one of which has a dis- 

 cernible basal part to the spiral thread; in the tentacles there is only one kind of nematocysts. The size of 



