HYDROIDA II 



J 93 



Corytte Loveni Perigonimus abyssi Campanulina turrita 



Tubularia regalis — roseus Tetrapoma quadridentatum 



Branchiocerianthus reniformis Eudendrium annulatum Campanularia speciosa 



Monobrachium parasitum Toichopoma obliquum 



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

 down as the Danish waters, and it would seem likely that it is identical with the polyp Coryne J ri- 

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

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

 drium annulatum 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 Branchiocerianthus reniformis is altogether unknown. We have 

 then remaining, as peculiar to Greenland, the species Tubularia regalis, Monobrachium parasitum, 

 Toichopoma obliquum, Tetrapoma quadridentatum, and Campanularia speciosa, high arctic or panarctic 

 species which appear to be of particularly steuothermic character. 



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

 species here are: 



Tubularia pule her Plumularia setacea Sertularella amphorifera 



Corymorpha nutans Polyplumaria flabcllata Diphasia attenuata 



glacialis Halicornaria campanulata Thujaria carica 



Zygophylax biarmata Cladocarpus bicuspis 



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

 cies, to wit, Corymorpha 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 given 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 

 ma)' be partly responsible for the somewhat less marked immigration of warmer atlantic species to 

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

 might well be the case. 



The Faroe Islands area is distinguished by only two species, Menu/a cornucopia and Eudendrium 

 Wrighti, 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 Tubularia regalis, Corymorpha glacialis, 

 Corymorpha groenlandica, Grammaria immersa, Stegopoma plicatile, and Sertularia Fabricii verge now 



The Ingolf-ExpeJition. V. 7. 25 



