HYDROIDA 



31 



Corymorpha nutans I\I. Sars. 

 1835 Coryiitorpint i/tifaiis, M. vSars, Beskrivelser og lagttagelser p. 7, PI. i, Fig. 3. 



The liydrocaulus, when extended, attains a height of 100 nun. It is broad at the hasi.s, attached 

 to the snl)stratuni by numerous rliizoids, and tapering upwards till it reaches its least breadth closely 

 below the polyjx The basis of the polyp is broad and surrounded by a iDroxinial whorl consisting of 

 up to 50 tentacles, which, when extended, attain a length of 30 nun. The distal tentacles are small 

 and placed round the orifice in a main whorl composed of several irregular circles quite closely set. 



The gonophores are developed into free medusae with four radial canals, one well-developed 

 tentacle and three rudimentary ones. The gonophores are developed on 15—20 blastostyles, arising 



200 tn. ^ ^ ^ — ~ ~ ~.b 00 m. .. —..... tooom. 2000 m. 



Text-fig. G. The haliitat of Corymorpha nvtmis in the Northern Atlantic. 

 (Ill the hatclied regions the litterature denotes a scattered, alltliongli couiiiion occurence). 



closely above the proximal whorl of tentacles. The blastost\les bear small alternating branches, each 

 provided with a large number of gonophores. 



Material : 



Iceland, 16 minutes N. W. Akranes, depth 26—30 fathoms (a couple of young polyps). 



The occurrence of the species is typically Ixircal. It is indigenous to the middle parts of the 

 littoral region. Towards the north it goes along the coast of Norway as far as Lofoten and towards 

 the south it penetrates to the northern parts of France. The species is recorded by J aderh ol m (1909) 

 from Matotschkin Schar (Nova Zembla) at the depth of between 2 and 5 fathoms. This find is most 

 peculiar and mvsterious. Corymorpha nutans occvu's not rarely in the North vSea, and I think Ilart- 

 laub (1907) is right in supposing the specimen from the North vSea recorded by me (1905) as a Cory- 



