HYDROIDA II ig. 



Coryne Lovcni PerigonimHs abyssi Campanulina turrita 



Tubulariu regalis — rose.us Tetrapoma quadridcntahim 



Braiichiocerianthus rcniformis Eudcndrimn aimulaium Campanularia speciosa 



Moiiohrachhtvi parasihtvi Toichopoma obliqintvi 



Of the species mentioned, however, Coryne Lovcni is also known from the North Sea as far 

 down as tlie Danish waters, and it would seem likel\- that it is identical with the polyp Coryuc Jri- 

 tillaria Steenstrup, and thus belongs to the Iceland fauna area. Pcrigoninms abyssi and Perigonimus 

 roseus extend southward along the west coast of Scandinavia at any rate as far as Bohuslan; Eudcn- 

 drittvi ammlafum has been recorded both in Norwegian and in British waters, and Campanulina tur- 

 rita has been found in Irish waters, near Belfast. In the case of these species it is thus natural to 

 suppose that they will also prove to occur in the intermediate areas at the Faroe Islands and Ice- 

 land. The geographical character of Braiicliioccrinntlnis m/iforiiiis is altogether unknown. We have 

 then remaining, as peculiar to Greenland, the species Titbularia regalis. Monobrachiutn parasitum, 

 Toichopoma obliquiim^ Tetrapoma qitadridoitatiim^ and Campanularia speciosa., hig^i arctic or panarctic 

 species which appear to be of particularly stenothermic character. 



A far more unexpected state of things is met with in the Iceland area. The characteristic 

 species here are: 



Tubiilaria pitlclier Phmiularia setacea ' Sertiilarella amphorifera 



Corymorpha nutans Polypbtmaria flabellata Diphasia attenuata 



— glacialis Halicornaria cavipamdata Thujaria carica 



Zygophylax biari/mta Cladocarpus bicjispis 



Among these there are, as far as our knowledge at present goes, two easterly, panarctic spe- 

 cies, to wit, Corxmorp/ia glacialis and Thujaria carica. These species thus characterise the Icelandic 

 fauna area as the frontier tract for east-arctic species. Similarly, the occurrence of the Greenlandic 

 Thujaria alternitheca suggests that the area in question is also a boundary region for westerly, arctic- 

 boreal species. The list gi\en is, however, most striking from the many exotic warm-water species 

 which it contains. The Iceland fauna area has, as a matter of fact, at present several more such 

 species than the Faroe Islands area. It would thus seem as if the influence of the warm atlantic 

 area upon the southern slope of the Iceland grounds is more immediate. How far the Rockall Banks 

 may be partly responsible for the somewhat less marked immigration of warmer atlantic species to 

 the Faroe Islands area cannot be stated with certaint\-, but there are several indications that such 

 might well be the case. 



The Faroe Islands area is distinguished b\- only two species, Merona cornucopice and Eudendrium 

 Wrighfi,as against the two other areas; these two species contribute, however, but little to the char- 

 acterisation of the waters in question as we know them at present. The most striking feature 

 of the true Faroe Bank area is another, negative character, to wit, the lack of high arctic or 

 panarctic species. Only deeper-living arctic species such as Tubtilaria regalis. Corymorpha glacialis, 

 Corymorpha groenlandica. Gram mar ia immersa. Stegopoma plicatile, and Sertzilaria Fabricii verge now 



The Ingolf-Expedition. V. 7. "^ 



