Section I. 



Literature and summary of the northern and arctic Zoantharia. 



'TpHE first species of Zoantharia (Zoaiithidae) described from northern waters was Ivpizoanthus incrn- 

 -*■ status, which forms colonies and lives symbiotically with Eupaguridae. This easily known spec- 

 ies was found on the Norwegian coast by Diiben and Koren, who in 1847 called it Mamillifera 

 incrustata. M. Sars (1851, i860) and Danielssen (1859) also observed this species from other localities 

 on the same coast. In the year i860 Sars mentioned a new species from Finmarken, which he 

 named Zoanthus arcticus and in 1868 Norman described from the Shetland Islands Z. incrustatus and 

 Z. anguicomus, the latter for the first time. A fonrtli species found in the Trondhjcm Fjord was 

 described by Koren and Danielssen in 1877 under the name of Zoanthus norvegicns. In the year 

 1877 Marenzeller mentioned Zoanthus arcticus from the regions round Smith Sound, which however 

 is identical with Epizoanthns lindahli described later in this paper, and in 1886 (p. 16) the same 

 author stated, that Palythoa norvegica had been dredged near Jan Mayen, a statement however which 

 proved to be incorrect, as the specimens on closer examination were found to be identical with or at 

 any rate closely related to Epizoanthns glacialis, a species described later by Danielssen. The 

 same year (1886, p. 52) C. Auri villins put forward a new species E. couchii unknown in the Nor- 

 wegian fauna, a statement however that could not be maintained, as the species in question is closely 

 related to Epizoanthns erdmanni of the present work and may possibly even be considered a variety of 

 the latter species. Thus, up to 1890 4 species of Zoanthidae living at the Norwegian coasts or in 

 the northern seas, namely, Epizoanthns incrustatus, E. arcticus, E. norvegicns and Parazoanthus 

 anguicomus, had been described in some detail, though very incompletely. 



During the period from i860— 1880 the well-known naturalist Verrill provided us with 

 information regarding some Zoanthidae from the coasts of North America. In the year 1864 he 

 described from New Jersey Zoanthus (Epizoanthns) americauus, which has later been met with very 

 often in the arctic regions, as far as Cape Cod and also in the region Cape Cod to Cape Hatteras 

 (Parker 1900, p. 757). In 1891 H add on and Shackle ton proved, however, that this species is 

 identical with Sars' F:. incrustatu.s. In the year 1882 another species of the North American Zoanthid 

 fauna became known, namely, Epizoanthns paguriphilns, first observed in deep water off the Nova 

 Scotian coast; like E. incrustatus this species forms carcinoecia. Further, Verrill mentions an incrusting 

 variety of E. americanus 11882, p. 316, 1883, p. 6), which he con.siders to be identical with Koren and 



TliL' ingolf-Expedition. V. 4. 



