148 



HYDROIDA II 



Thujaria carica Levinsen. 

 1893 Thujaria carica Levinsen, Meduser, Ctenophorer og Hydroider, appendix, pi. 7, figs. 26—29. 



The upright colonies are pinnate in their basal parts, spirally coiled in the distal, with bran- 

 ches secondarily somewhat ramified dichotomously; the symmetrical plane of the branches is vertical 

 in the pinnate parts, but horizontal in the spiral. The stem has two single, opposite longitudinal rows of 

 hvdrothecse; there are two to five, generally three hydrothecse between two successive branches on the 

 same side of the stem, the lowest in the branch angle. The branches are divided into irregular inter- 

 nodia with four to eight hydrothecse on each; the hydrothecee are set subalternately in two opposite 

 longitudinal rows, their plane of symmetry coinciding with the broad plane of the branch. The hydro- 

 thecse have a large free distal part; the length of the free portion of the adcauline wall exceeds the 

 diameter of the opening, and is between one-third and one-half the length of the hydrotheca itself; 

 the opening margin is smooth, without sinus, with a round opercular plate abcauliually fixed. The interval 

 between two hydrothecse in the same row varies somewhat, but is never less than the opening diameter. 



The gonothecse are set on the upper side of the branches in the spiral parts of the colonies. 

 They are asymmetrical oval to pear-shaped, with a rudimentary neck and broad, round opening. 



Material: 



"Iugolf" St. 143 62°58' N., 7°09' W., depth 388 fathoms, -f- 0,4° 



"Thor" 66°i9' N., 23°i4' W., depth 115— 120 metres [labelled Thujaria lonchitis\ 



Iceland: 32 miles S. of Selvogstangar, depth 170 metres. 



Kara Sea "Dijmphna" [type-specimen |. 



Thujaria carica is an arctic species known from the waters between Spitzbergen and Beeren 

 Island to the New Siberian islands; in the high arctic tracts it belongs to the upper third of the 

 littoral region. South of the range mentioned, the species has hitherto only been found at the south- 

 west point of Iceland, and north of the Faroe Islands, where it moves down into the abyssal region. 

 Up to now, it has not been recorded from Greenland, and thus appears to be an easterly arctic species. 



Thujaria sp. aff. distans Fraser. 

 Material : 



"Ingolf" St. 85, 63°2i' N., 25°2i' W., depth 170 fathoms 



The small Thujaria colonies from the "Ingolf" St. 85 very much resemble Thujaria carica, and 

 may possibly prove to belong to that species; there are, however, certain points of difference which 

 render the identity somewhat doubtful, and for the present, these colonies should doubtless be kept 

 apart from Thujaria carica. It is not unlikely that they really represent a distinct species, but as the 

 colonies are quite small, and without gonangia, it is very difficult to give a thorough characterisation. 



The colonies are pinnate, with simple branches. The stem, which is monosiphonic, is divided 

 into irregular internodia, and lacks both branches and hydrothecse on its lower part. A couple of centi- 

 metres from the base, the hydrothecse begin to appear; they are set as a rule alternately in two op- 

 posite longitudinal rows. The stem is slightly zigzag, and has on its upper part, besides the hydro- 

 thecse mentioned, also alternating branches; the largest colony which is of quite regular build has 



