22 Hjalmar Ostergren. [No. 9 



fauna in the „Yaagsfjor(i og Ulvesund, ytre Nordfjord". The Nord 

 Fiord hes altogether south of 62° N.; Vaags Fiord and Ulvesund lie 

 at the mouth of the same. But seven whole degrees further north 

 there is another Yaags Fiord, and it is at this place Ludwig has 

 located Geieg's researches. This mistake, which is so easily ex- 

 plained, has brought confusion in the statements regarding the distri- 

 bution of the different species towards the North. As above (p. 

 8) has been shown, the statement by Danielssen & Koren^, that 

 Thyone fusus should have been found at Rost 67° 30' N., is also 

 incorrect. 



Amongst the 17 species of Holothurians in the north of Nor- 

 way eight must be considered as boreal (or subarcticj: SticJio- 

 pus tremuhis, Bathyplotes natans, Mesoihuria intestinalis, Cucuma- 

 ria hispicla, Psoliis squamatiis, Syiiapta inhærens, Lahidoplax huski 

 and Myriotrochiis vitreus. Five of these I have hitherto only seen 

 represented from the comparatively warm West Fiord or neighbou- 

 ring districts: Bathyplotes natans^ Mesothuria intestmalis, Cuciima- 

 ria hispida, Synapta inhærens and Myriotrochiis vitreus. Probably 

 one or the other of these species extends along the open coast 

 (not in the fiords) still further north towards the North Cape. If 

 Psoliis squamatus is to be found at all in northern Norway, it is pro- 

 bably also confined to this district. Of Stichopus tremulus and Lcdn- 

 doplax hiisJii I have seen specimens also from East Finmark (east of 

 the North Cape), and these two are probably to be met with on the 

 Murman Coast. According to statements made by some authors 

 (cf. Ludwig 1900) Ciicumaria hispida and Psolus squamatus have 

 been found right up to the Barents Sea, the latter species and 

 Mesothuria intestinalis on the Murman Coast. With regard to the 

 two first mentioned species, these statements are due to mistakes 

 in the determination (cf. p. 8, 10 and 11). With regard to Meso- 

 thuria intestinalis further evidences are to be desired. 



Four species have a wide distribution within the Arctic as well 

 as within the Boreal region and can therefore be regarded as 

 common to both: Cucumaria frondosa, Phyllophoriis pellucidus, 

 Ph. drummondii and Psolus phantapus. They are, possibly with 

 the exception of Phyllophorus drummondii, to be found distributed 

 over the whole of Finmark. 



Five species are to be considered as arctic: Trochostoma 

 boreale, Anhjroderma jeffreysii, Chiridota lævis, Myriotrochus rinJcii 



