28 



HYDROIDA 



one individual to another in a larger colon_v, and individuals with quite smooth stems are not seldom 

 observed in colonies wliich are otherwise typical Tubiilaria larynx. The dimensions of Tuhiilaria Iniiiiilis 

 wdioUy agree with those of young colonies of Tuhiilaria larynx, and the numbers stated as characteristics 

 stand far within the range of variability known in this species. Then only remains the condition of 

 the blastostyles, which should be erect in Tubiilaria Iiiii/iilis, but hanging in Tuhiilaria larynx. An 

 examination, however, of living material will show that only in rare cases the blastostyles of Tuhiilaria 

 laryjix can be described as hanging (comp. Broch 1911); on the contrary they are generally borne in a 

 rather erect position, particularly when not yet very large. Thus also this criterion proves to fail, 

 and consequently we are forced to consider Tuhiilaria liiii/iilis as a s\'nonyme of Tiihttlaria larynx. 



Tubiilaria larynx is an entirely boreal species, which has its main occurrence in the zone of the 



20c m. __. boom ._ «.„._.iooo/Ti. 2 ooo m. 



Text-fig. F. The distribution of Tubiilaria larynx in the Northern Atlantic. 



laminaria and the red algae. Towards the south it enters into the Mediterranean, and towards the 

 north it penetrates as far as Nova Zenibla, and seems still to occur at Spitzbergen. On the south- 

 western coasts of Iceland it is very frequent, and it is also found on the east coast of North America. 

 It is to be wondered that the species has not yet been met with at Greenland. 



Tubularia sp. indet. 



Stems of Tuhiilaria of the type indivisa-rcgalis are in hand from the following localities: 



"Ingolf" St. 8. 63°56' N., 24°4o' W., depth 136 fathoms, + 6°o C. 



- - 35- 65°i6' - 55^05' - - 362 - + 3°6 - 



- - 36. 61V - 56°2i' - - 1435 - + i°5 - 



