combination. 



239 



Depth: — I'O 



Temp.: — (i.n O.J 



Sal.: — 3;5..-.<i M.u 



.■U.:!ii 



.M.l 



iiinlii. Piiii... wliicli 



A little farther in tiie tionl. Liinoii 

 a boreal lonn, was taken, aceordiiiy to Fhiklk. 



In the Taiia and Varang-er Fiords, .such eompaiatively IiIkI' 

 temperatures at tiie bottom as 2.8 and 3.1 (p. 20) have also been 

 resristered. So that one must not expect to find an altotrether 

 unmixed ai-ctic fauna in East Finmark cither, although the arctic 

 forms are greatly in the majority. Such species as Perten fitjrinus, 

 Venus ov(it(( and (/(itHiHi. Dentalutm entalis. Patina iiellucida, Gih- 

 buhi cineraria and tiinnda, Natira inontaijui etc. must be con- 

 sidered to be decided boreal forms, and yet they have puslied their 

 Avay up to East Finmark. 



Professor G. O. S.vrs has found several boreal forms at Hasvik 

 in Sorø. This place has not been hydrographically investigated, 

 but 1 am inclined to think that the deep channel, which penetrates 

 in from the ocean along the island, has comparatively warm water 

 at the bottom. Another stopping place for boreal forms is the 

 Malangen, where the bottom temperatui-e at the greatest depths 

 varies between 4 and 5".5 C. but the Vest Fiord is the most 

 definite limit for marine fauna on the Norwegian coast, a very 

 large number of boreal animal forms being found here, but not 

 further north. It is interesting to be able to connect this fact 

 with the one that the Vest Fiord is the most northerly of the large 

 Norwegian fiords in which ocean water dominates the natural conditions 

 at the depths (t = — 7°, s = ca. 35 %o). As a general zoogeo- 

 graphical result, it may be stated that, Avith respect to the large 

 important fiords, whicii are open to the ocean, tiie lusitanic and 

 boreal forms occur as far up as the Vest Fiord in larger numbers 

 than the arctic ones. It is first in the Malangen that the arctic 

 forms are in the majority, and this even more noticeable in the 

 Kvænangen and Porsanger Fiords, the latter having almost unmixed 

 arctic fauna. The inner parts of the fiords and the branch fiords 

 have retained more of the arctic .species. For instance, while in 

 the Salten Fiord, the southern forms are in the majority, we find 

 that in the Skjenstad Fiord, which lies further inland, and in the 

 Beier Fiord whicli is a little farther south, the arctic animals are 

 more profuse than the southern ones. The Rauen Fiord has not 

 yet been investigated, but it is probable that also there arctic forms 

 will be predominant. 



Generally speaking, these facts coincide with the opinion ex- 

 pressed long ago by Prof. G. 0. Saes.') What I have tried to 

 adduce is the connection between zoogeographieal and hydrogra- 

 phical limits. 



The northernmost Lophohelia reef, hitherto known. 



In his description of Ophiacantha spectahiUs. G. (J. Sars-) 

 says: — „I have found this important species at one place only, 

 namely near Bodo, where it is not so very scarce between the 

 corals (Lophohelia proUfera), which are abundant at a depth of 

 from 80—100 fathoms. It is generally so firmly attached to the 

 tangled branches of the corals, by means of its spiked arms, that 



it is exceedingly difficult to get it loose." On June 19th 1878. the 

 Norw, North Atl. Exp. took two specimens of this echinoderm at 

 St. 255 in the Vest Fioi.l (cs" i-_>' N., 15" 40' E.). The depth 

 is given as being (\2i ml is., ti-niperature ()..5 and the bottom 

 matei'ial. clay. 



About the sMuic time. O. sjiertuhilis was found by \". S-|"ii.m 

 in the outer part of the Troudhjem Fiord. In a paper wiitteii 

 in recent years Stok.m') says that this species occurs in largo 

 quantities on Lophohelia proUfera in the outer part of the Troud- 

 hjem Fiord. According to Gkikg,-) also Hoyle has mentioned 

 the species from the Faeroe Channel (433 fathoms). I do not 

 know if Lophohelia proUfera is found at the latter place, but it 

 is veiy probable, for M. Sars') mentions that it is found off llie 

 Shetland Isles. Verrili/) too mentions spectahiUa as found off 

 Nova Scotia, 1883, 131 fathoms, one specimen. Nothing is said 

 about 0. apectahiUs having been found together with Lophohelia 

 proUfera, but in another place, Verrill writes (1. c. p. 53(i): ,.L. 

 proUfeia B. range, 100 to 300 fathoms, off Nova Scotia; lOUO 

 fathoms, dead, 1884, rare." There is thus probably nothing which 

 makes it unlikely that the ophiurid in question may have l)een 

 attached to the coral here mentioned. 



When working out my material of echiuoderms, Grieg'^) mentions 

 that KoEHLER has given 0. s2)ccfabilis as being found in the Bay 

 of Biscay, but as Koehlee's specimens appear to be somewhat 

 different to Sahs's species, Grieg raises doubt as to their identity. 

 The following table gives some important data concerning the places 

 where I have found spectahiUs. 



0. spectahiUs, G. 0. Sars. 



) Nogle bemerkninger om den maiim; faun 

 lige kyster. Tromsø Mus. Aarsli., II, 1879. 



^) Nye Kchinodermev fra den norske Kyst. 

 Selsk. Forh. 1871. 



Se,,., p. 12. 



Arno is situated outside the mouth of the Salten Fiord near 

 Bodø, and Tranodybet is a little farther in than st. 255 of the 

 Norw. North Atl. Exp. in the Vest Fiord, the bottom here is 

 given as being of clay, but there has probably been a hai'd spot 

 which is , accounted for by the presence of Lophohelia, which was 

 the case in Ti'anodybet. 



There is thus reason to conclude that 0. spectahiUs is so closely 

 connected with Ijophohelia proUfera as to make the latter almost 

 a necessity for the former. This does not, however, at all inqily 

 that where ever Lophohelia occurs, 0. spectahiUs is also found. This 

 is an interesting instance of one animal's dependence upon another. 



') Oversigt over Trondh.jemsfjordens fauna. Beretning fra arbeidskomiteen 

 for Trondlijenis biologiske .station 1900. 



3) Ophiurioidea, p. 24. The Norw. North Atl. Exp. 



") Fossile dyrelevninger fra Quartærperioden, p. 92. 



♦) Results of the Explorations made by the steamer Albatross. 



Ann. Rep. of the Comm. of Fish and Fishery for 1883. 



5) Oversigt over det nordlige Norges echinodermer. Berg. Mus. Aarb. 

 1902. n,). 1. p. 14. 



