. ACTINIARIA 



Gonactinia prolifera (M. Sars.j Sars. 

 Actinia prolijera n. sp. M. Sars 1835 p. 3, 11 PI. 2, fig. 6. 



Gonactinia prolifera Sars, M. Sars 1851 p. 142, 1853 p. 379, 386. Danielsen & Koren 1856 p. 87. Koren, 

 1857, p. 93. Andres, 1883, p. 366. Blochmann & Hilger, 1888, p. 385, PI. 14, 15. 

 Haddon, 1889, p. 340, textfig. 2. Prouho, 1891, p. 247, PI. 9, figs, i — 3. Carlgren, 

 1893, p. 31, PI. I, fig. 14, PI. 4, figs. 11—13; 1904. P- 546, fig- I- Appellof, 1893, p. 27. 

 1895, p. II. Grieg, 1913, p. 143. Kerb, 1913, p. x. textfigs. 1—5. Pax, 1915. 



Diagnosis: Tentacles 14 — 18 commonly 16, of about the same length as the column, almost all 

 of the same size. Actinopharj^nx of about half the length of the column with longitudinal furrows corres- 

 ponding to the insertions of the mesenteries. Siphonoglyphes a little differentiated with aboral prolonga- 

 tions. Spirocysts in the ectoderm of the column about 17 — 22 X 2,5 ^, in the tentacles 13 x i — 24 X 2,5 ji. 

 Actinopharynx without spirocysts. Nematocysts in the ectoderm of the colunm about 17 — 29 x 2,5 — 3 fi, 

 in the tentacles partly 22 — 24 X 2 ^, partly 29 — 43 X 3,5 — 4 //, the latter numerous in the distal part. Only 

 the 4 lateral " Edwardsia-i-nesentenes" with both reproductive organs and filaments. Directive mesen- 

 teries and often the 5th couple with filaments. Mesenteries of the second cycle only common in the 

 dorsolateral exocoels. Arrangement of the mesenteries often irregular (compare above!). lyongitudinal 

 muscles of the mesenteries and the parieto-basilar muscles very weak. No stomata. 



Colour: Flesh-coloured or white with transparent inner organs. 



Dimensions: Length of the column and the tentacles about 0,3 cm. 



Occurrence: Sweden. Gullmarfiord in several places attached to sea- weed, Serpula- tubes or mussel- 

 shells (Carlgren). Vaderoarne (Zool. Stat. 1911) to shells of Lima, Kosterfiord. Hamnholmen 106 — 80 m. 

 (Zool. Stat. 1910). North-Sea without distinct locahty (Uddstrom). 



Norway. Coast of Bergen, the islands off Bergen and the outer parts of the fiord. Sols\'ik Bergen 

 20 — 30 m (Kerb), Herlofiord (teste Appellof), Hardangerfiord, Straumastein, Saetvetnes 10 — 25 m (teste 

 Grieg), Slaetholmen (M. Sars), Bougestrommen, Manger (M. Sars), Gibostad (Dons), Hammarfest M. Sars). 



Coast of Murman, Olenja Guba littoral (teste Pax). 



Further distribution: Mediterranean (Prouho). 



Remarks: This species has been described before in detail by Blochmann and Hilger 1888 and 

 by myself 1893. 



Concermng the distribution and size of the stinging capsules I will state as follows : In the ectoderm 

 of the column there are nematocysts as well as spirocysts, rather numerous, the size of the former variates 

 from about 17 — 29 X 2,5 //, the latter from about 17 — 22 X 2,5 ^, possibly there are also smaller spirocysts, 

 what I have not been able to decide. In the ectoderm of the tentacles the spirocysts appear everywhere in 

 great numbers, they variate from about 13 x i /i to 24 X 2,5 /<. The nematocysts were of two different sizes, 

 partly smaller and not so numerous, 22 — 24 x 2 ^, partly larger, 29 — 43 X 3,5 ,u. On one part of the latter 

 the basal part of tlie spiral thread was discernible. As in Protanthca the greater part of the large nemato- 

 cysts were concentrated in the summit of the tentacles, further down they were much fewer in numbers. 

 The distal part of the tentacles also forms rather strong batteries of nematocysts. I have not been able 



