438 G. M. R. Levinsen. 



In most zooecia of the small fragment the distal wall is provided 

 with a small rounded pore-chamber of the same structure as those 

 found in Scrup. scabra. I have not seen such a pore-chamber in 

 specimens from other localities. 



Station 95 a. The Sound between Renskæret og Maatten, 50 — 

 100 m. 



Fam. Membraniporidae. 



Membranipora (Electra) catenularia Jameson. 



Flustra membranacea O. F. Müller, Prodromus Zool. Danicae, p. 253. 

 — — Abildgaard, О. F. Müller, Zool. Danica, vol. 3, 



p. 63, tab. 117, figs. 1, 2. 

 Tubipora catenularia Jameson, Wernerian Mem. p. 561. 

 Membranipora pilosa, forma catenularia (M. catenularia) Smitt, op. cit. 



1867, pp. 370, 417, pi. 20, figs. 45—38. 

 Membranipora catenularia Hincks, British Marine Polyzoa, p. 134, pi. 



17, figs. 1—2. 



— monostachys var. a (fossaria) Hincks, eod. loco, p. 132, 



pi. 18, figs. 3, 4. 



— tenella Hincks, A General Hist, of the Marine Po- 



lyzoa (Annals Nat. Hist. 5. ser., vol. 6, 

 1880, p. 376, pi. 16, fig. 7). 



— catenularia Levinsen, Mosdyr, Zool. Danica, 4. В. 1. 



Afd., 1894, p. 56, Tab. IH, figs. 37, 41. 



— monostachys Waters, op. cit. 1900, p. 59, pi. 8, fig. 3. 



— MUlleri Bidenkap, Die Bryozoen, Fauna arctica, 1 Cheil. 



1900, p. 532, Tab. IX, fig. 1. 



— — Norman, Notes on the Nat. Hist, of East Fin- 



mark (Annals Nat. Hist. ser. 7, vol. 11, 1903, 

 p. 586, note. 



This species is one of the only three species of cheilostomatous 

 Bryozoa in which a calcareous operculum has hitherto been found. 

 It is interesting, moreover, in being the only Bryozoon found in the' 

 innermost part of the Baltic, while at the same time it is widely 

 spread in the arctic seas. While at Spitzbergen it lives in a depth 

 of 9 — 20 fath., it has been found in the boreal sea outside of Nor- 

 way in a depth of 200 — 300 fath.; and at Copenhagen I have found 

 it in the "Stadsgraven and the Kalvebodstrand" in water of a very 

 small äegree of salinity and in a depth of less than one foot. Smitt 

 has already pointed out that the baltic form of this species must 

 doubtless be regarded as a relict. 



We may discern two varieties, namely the var. fossaria in which 



