ii8 



HYDROIDA II 



The Faroe Islands: 8—10 miles N. of the Faroe Islands (without further details) 



6 miles N. by W. of Store Kalso, depth 60 fathoms 



7 — N. by E. of Myggen^s point — 57 — 

 BoronEES 13/4 miles in N. 75°W. — 30 — 

 Deep hole at north point of Nolso — 100 — 

 13 miles W. by S. of Munken — 150 



I have in earlier works (1908, 1909) united this species with the next, the more finely built 

 form Abietinorin filicnla (Ellis et Solander), having overlooked the specific character which lies in the 



200 fti, ^ 6 00 m. .» ._(ooom. z ooo m. 



Fig. LXU. The distribution of .■iiie/tnaria abietina in the Northern Atlantic. 

 In the hatched regions a common occurrence is reported. 



peculiar diaphragm of Abietinaria abietina^ as pointed out by Levinsen (1893 p. 56). Generally speak- 

 ing, the robuster stucture of the colonies will obviate any doubt when dealing with the last-named 

 species, but this is not always the case. Occasionally, ^{bictinaria abietina may assume a finer struct- 

 ure (cf. Broch 1908) and it was from observation of such doubtful colonies that I was led to combine 

 the two species under a common name. In such dwarf colonies, however, identity may easil\- be deter- 

 mined by examination of the diaphragm, which in Abietinana abietina is typically bilateral, whereas 

 in Abietinaria Jilieitla the development is almost entirely radially synnnetrical. 



Abietinaria abietina is a circumpolar boreal species, capable of penetrating far into the arctic 

 area, albeit its occurrence there is more si)oradic. It can also move far to the south, and is found 

 in the Mediterranean and at Madeira. It belongs really to the littoral region, but mav exceptionally 



