HYDROIDA 



53 



Perigonimus repots is a southern species which penetrates into our seas. It has been recorded 

 from the Mediterranean and the west coast of France, and occurs frequently in the sea round Great 

 Britain and Ireland. Already in the North Sea its occurrence is more straggling. In the Danish 

 waters and along the coast of Bohuslan it is still rather frequent. On the coast of Norway it is not 

 unfrequently met with in the Trondhjemfjord, where the fauna, on the whole, bears a southern char- 

 acter. But only once it has been found farther to the north, at Lofoten. Ssemundsson (1911) re- 

 cords several questionable specimens from the west and the north of Iceland. But these localities 

 have to be confirmed. As a new locality must now be added the Faroe Islands. The species belongs 

 to the litoral region. 



too m. 



2 coo m. 



Text-fig. P. The distribution of Perigonimus repens in the Northern Atlantic (o localities needing further confir- 

 mation. In the hatched region the litterature denotes a scattered although common occurence of the species). 



Perigonimus abyss! G. O. Sars. 



1874 Perigonimus abyssi, G. O. Sars, Bidrag til Kundskaben om Norges Hydroider, p. 96, pi. 5, Fig. 2730. 

 1911 sp., Kramp, Danmarks-Ekspeditionen til Gronlands Nordostkyst, p. 363. 



From the reptant stolons proceed unbranched polyp stems, which attain a length of 1.5 mm. 

 The polyps are about 0.5 mm. long, broadly fusiform, bearing 58, usually 7 tentacles in a whorl. 

 Below the tentacles the polyp is surrounded by a rather vigorous, wide, jellied pseudohydrotheca, which 

 is, however, often hardly visible on the polyp wholly extended. The polyp stems are irregularly and 

 strongly wrinkled, and have a dark-coloured, vigorous perisarc. 



The gonophores are developed into free medusae, having, when deliberated, a vigorously 

 developed umbrella and four tentacles. The gonophores are developed on the polyp stems, to which 

 they are attached by a very short stalk. On the polyp stem arise one or two gonophores. 



