Combination. 



•2 11 



known in the deep water between the Hebrides and the Faeroe 

 [sles, in Portugal, the Azures and Senegambia." 



From the investigations made by M. and (I. ( >. Saks, as well 

 as V. Storm, we have a tolerably complete knowledge of the 

 fauna of the coral regions in our fiords. Storm lias given a con- 

 cise account of the conditions in the Trondhjem Fiord, with a map 

 showing the position of the corals, and to this 1 would beg refe- 

 rence. I will here also emphasize the fact that the characteristic 

 forms mi the epiglacial Lophohelia-reef at Drohak (Pecten vitreus, 

 P. aratus, Lima excavata, Area noihtlosn etc.) also at the present 

 time show themselves to be faithful companions. However. I do 

 not think practical boundaries can be drawn between the fauna 

 which are connected with Lophohelia and those which are connected 

 with other corals, such as. Paragorgia arborea, Paramuricea placomus 

 or Primnoa lepadifera. 



It may. on the other hand, be said that the region of the 

 deep water corals has its definite, decided fauna, which is parti- 

 cularly uniform in all the large Norwegian fiords to which the 

 ocean water has tree access, from the Bokn to the Vest Fiord. 

 There is a coral facies of animals, just as there is a claj facies. 



A few words on the fauna in clay. 



'fin' deep channels and basins in the fiords (150—200 m. and 

 more), of which clay forms the bottom and into which the ocean 

 water has access, have also their characteristic animal life. 



And since the investigations made by G. 0- Sars, in the 

 sixties, at the fishing place Skroven and at other places in the 

 Vest Fiord, we know that there are especially interesting forms on 

 the (day-bottom of the depths. Such as. for instance. Isidella hip- 

 puris, Ulocyathus arcticus, Rhizocrinus lofotensis, Brisinga coronata, 

 Flustra abyssicola etc. The fauna at Skroven, where I have made 

 a very successful haul with a trawl at a depth of 350—410 m., 

 is very rich. In addition to the forms .just mentioned, it was quite 

 usual to find such species as the following, on the clay depths in 

 the Vest Fiord and those of its arms iido which ocean water pene- 

 trates at the bottom: — 



Foraminifera : — Astrorhiza arenaria, Saccammina sphwrica, 

 Storthosphoera albida, Bathysifon filiformis, Rhabdammina abyssorum. 



Echinodermata : -- Amphilepis norvegica, Ophioscolex glacialis, 

 Psilaster andromeda, Stichopus tremulus, Bathyplotes natans, Meso- 

 thuria intestinalis, Cucumaria Mspida, Myriotrochus vitreus. 



Polychmta: - - Lmtmonice filicornis, Leanira tetragona, Terre- 

 bellides stromi. 



Moliusea: — Nucula tumidula, Portlandia lucida, Malletia 

 obtusa, Ann pectunculoides, Limopsis minuta, Cardium minimum, 

 Kelliella milliaris, Syndosmya-sfeeies, Necera obesa, X. rostrata, 

 Dentalium occidentale, />. agile, Siphonodentulium quinquangulare, 

 Scaphander lignarkts. 



Ostracoda: — Cypridina norvegica. 



Tsopoda: — Hunnopsis typica, Eurycope cornuta. 



Schizopoda: -— Boreomysis tridens, Pseudomma roseum. 



Decapoda: — Pontophilus norvegicus, Munida rugosa, M. tenui- 

 mana. 



Ascidia: — Ascidia gelatinosa. 



The above list gives some of the species which are constantly 

 found on the clay at the bottom of rather deep water. Many of 

 these forms are undoubtedly mud-eaters, more especially is this the 

 case with reeard to the above mentioned Holothurioidea. Some of them 



appear to lie dependent upon ocean water it = 6—7° ('., s = about 

 35 %o). According to Ostergren, 1 ) Bathyplotes natans, Mesothuiia 

 intestinalis, Cucumaria Mspida and Myriotrochus vitreus are not 

 found in Norwegian fiords further north than the Vest Fiord. It 

 is characteristic that I took several specimens of Bathyplotes natans 

 and Mesothuria intestinalis in the Salten Fiord where the tempe- 

 rature was <i".<;;> ('. and the salinity 35,13 %o, while in the 

 Skjerstad Fiord, which is only a little further in. where t = 3°, 

 •_' and s - 34 ".,>,.. not a single specimen was to be seen in all 

 the dredgings made. Bathyplote-i occurs in rather large numbers 

 at its northern limit; at the station at the mouth of the Folden 

 Fiord at a depth of 530 in.. 20 individuals of this species were 

 taken, hut only 4 Mesothuria. Of clay-oottom molluscs, which have 

 not hitherto been found north of Lofoten, the following may be 

 mentioned: — 



Mull, I'm obtusa, Kelliella milliaris, 'Dentalium agile, Scaphander 

 lignarius etc. The deepwater fauna on the mud-bottom is remark- 

 ably uniform in the large fiords which are filled with ocean water, 

 from the Bokn Fiord to the Vest Fiord, nothwithstanding that the 

 Vest Fioi'd and its adjacent fiords contain some forms which are 

 wanting in the Bokn Fiord. Further investigations will probably 

 equalize this apparent difference to some extent, for instance, I 

 have latterly found Rhizocrinus lofotensis also in the Bokn Fiord. 

 But it will probably he found that such a species as Ulocyathus 

 arcticus cannot be included among the fauna of the Bokn Fiord, 

 this species must, judging from what is up to the present known 

 with regard to its distribution, be considered to be an arctic species, 

 which has been able to exist under the natural conditions deter- 

 mined by the ocean water which penetrates into the fiords. On 

 the wdiole, one may say that, zoogeographically speaking, the deep 

 water fauna on the clay-bottom of the fiords in question are spe- 

 cially remarkable on account of the large number of forms in them 

 which have a wide distribution southwards. But, north of Lofoten, 

 the fauna on the clay have cuite another character. The southern 

 forms disappear, and the northern ones take their place. At my 

 stations in the Lyngen Fiord (Lyngen II and III) at the re- 

 spective depths of -J5it and 320 m. on clay-bottom such forms as 

 the following occurred in large quantities : - Ctenodiscus crispatus, 

 Myriotrochus rinM, Pecten groenlandicus and Astarte crenata. Here 

 too were found Siphonodentalium vitreum, Scalaria groenlandica, 

 Bela exarata etc. The peculiar arctic Bryozo. Alcyonidium disci- 

 forme, was also taken here. Diastyl'ts goodsiri. Pseudomma trun- 

 catum and many other arctic forms also occurred. At the station 

 Lyngen II, d == 250 m., t =-- 2°,85 ('.. s = 34,47 %o, and at 

 Lyngen III, d = 320 m., t = 3 n ,65 C. and s : .".4,84 % . 

 At both stations in the Lyngen Fiord, several specimens of two 

 actinia species were taken, but none were conserved. If I remem- 

 ber rightly, they were Actinostola callosa and Bolocera tuediae. 



Edwardsia andresi and Epizoanthus erdmanni were also found. 

 As I have previously mentioned, there is another character over 

 the fauna in the deep waters of the Malangen Fiord, and if we go 

 as far as to Lyngen and Kvsenangen, the difference is even more 

 striking. In the deep waters of Kvsenangen where d = 343 m., 

 t = 2°,3 C. and s = 34,49 %o, were found, for instance. 

 Myriotrochus rinki, Polychmta, e. g. Harmothoe rarispina, Nephthys 

 malmgreni, N. ciliata, Nicomache lumbricalis, Terebellides stromi. 



Moliusea : — Pecten groenlandicus, Area pectunculoides, var. 

 septentrionalis, Astarte crenata, Siphonodentalium vitreum etc. 



M 'l'li.' Holothurioidea of Northern Norway. Berg. Mus. Aarb. 1902, No. 9. 



31 



