54 



HYDROIDA 



Material : 



Greenland, Egedesminde (on Lepeta coeca). 



The species has been found chiefly along the west coast of Scandinavia. It is likely to occur 

 much more frequently than might be believed from the scattered data. On account of its small 

 dimensions, and as, besides, it prefers settling on living, smaller molluscs, it too often escapes the 

 attention of the investigators of hydroids. Perigonimus abyssi has been found at Bohuslan and 

 on the west coast of Norway, from Stavanger as far as the Trondhjemfjord, at the depth of ioo 

 —600 metres. On the north side of Beeren Island it has been met with at the depth of 165 



Text-fig. Q. The finds of Perigonimus aiyssi in the Northern Atlantic. 



metres (Bonne vie 1899). In Arctic regions it may occur in considerably shallower waters. Thus the 

 German expedition to Spitzbergen in 1898 found the species in the Storfjord at the depth of between 

 o and 10 metres (Broch 1909), and certainly it is the same species that is recorded by Kramp (1911), 

 by the name of Perigonimus sp., from the depth of 20—40 metres at a couple of stations of the "Dan- 

 mark" Expedition. To the localities previously recorded must now also be added the west coast of 

 Greenland near Egedesminde. -- According to the data in hand, the species must be characterized as 

 Arctic and boreal (Text-fig. O). 



Perigonimus roseus (M. Sars) Bonuevie. 

 1874 Rhizoragium roseum, M. Sars in: G. O. Sars, Bidrag til Kundskaben om Norges Hydroider, p. 96. 

 1892 Garvcia groenlandica, Levinsen, Meduser, Ctenophorer og Hydroider fra Groulauds Vestkyst, p. 13. 

 1898 Perigonimus rose/is, Bonuevie, Neue norwegische Hydroiden. 

 1911 Garveia groenlandica, Kramp, Danmark-Ekspeditioneu til GronlandsNord6stkyst,p.363, pi. XXV, fig. 6. 



