HYDROIDA 



25 



Tuhulnria iiidivisa being globular, and accordingly broadly rounded in tlie distal part, while that of 

 Tnhiihina regalis is oval and showing an attempt to be pointed in the distal part. 



Tuhularia iiidivisa has a ver>- wide distribution. Its main occurrence in the boreal seas is bound 

 to the middle and deeper parts of the littoral region and to the upper part of the deep sea region. 

 From the cold area we find the species but once recorded, by Grieg (1914). After the examination 

 of his specimens I cannot confirm this record; the specimens consisting only of hydrocauli without 

 polyps, more probably belong to another species of Tuhuhiyia inhabiting the deep sea. 



To judge from literature, I'libiihirid iiidivisa penetrates rather far into the shallower parts of 

 the Arctic regions, where it is recorded even from the New .Siberia Islands (Jaderholm 1908). How- 

 ever, as appears from what is stated above, there is a possibility tluU .some of the Arctic individuals 



T(j.\t-fij^. I). Till- (listrilnitioii of Tiibulan'a indivisa in the Norlliern AUaiUic. 



are in fact to be referred to 'ruhitlaria rciialis. — The species also penetrates far towards the south. 

 It is recorded by Fewkes (18S1) even from the Caribbean Sea, by A 11 m an (1877) from between Cuba 

 and Florida, and by I'.illard (1906) from the west coast of Africa. As Tubiilaria iiidivisa is recorded 

 at the same time both fnmi the I^ast and the West coast of North America, it must be characterized 

 as a circumpolar or rather "circumboreal" (Nordgaard 1912) species. 



Tubularia regalis Boeck. 

 i860 Tubularia regalis Boeck, Videnskabsselskabets I"\)rliandlinger for 1859. 

 1899 — — -)- T. variabilis Bonne vie, Nor.ske Nordhav.s-Expedition, p. 24. 



Colonies who.se long, dark-brown-colourcd iiydrocauli are in the lower jiarts twisted together. 

 The stem is covered with a \igorous periderm, but shows no rings nor wrinkles. No collar is formed 



The Infjiilf-Kxrcdition. V. 6. 4 



