HYDROIDA II 



121 



Stifflv built, pinnate, dark-brown colonies with undivided l^ranclies. The stem, which is niouo- 

 siphonic, is divided up into irregular iuternodia, and has two single longitudinal rows of hydrothec£E 

 and two rows of alternating branches; there are three hydrothecce between two successive branches 

 on same side of the stem, the lowest in the branch corner. The branches have two rows of very closely 

 packed hydrothecse, the hydrothecce in the single longitudinal rows have their oral parts alternately 

 turned to either side, making a distinct approach to quadriserial arrangement, and the branches thus be- 

 come almost quadrilateral in section. The hydrothecse are small, entirely embedded, without any free 

 distal part of the adcauline wall; the opening margin forms an adcauline sinus, in which the large 

 opercular plate is attached. The hydrotheca opening is comparatively very large. 



., 200 m. boom. 1000 m. 2 ooo m 



FiCT. LXIV. The occurreuce of Abietinaria (^Jftisca in the Northern Atlantic 

 (In British waters the data are somewhat vague, biit note a rather common occurrence). 



The gonothecce are set on the upper side of the branches. They are pear-shaped, with 

 short stalks. 



Material : 



■'Ingolf" St. 55 63''33' N., i5°o2' W.; depth 316 fathoms, 5,9° 

 The Faroe Islands: 7 miles N. by E. of Myggenses point, depth 57 fathoms 

 6 — N. by W. of Store Kalso, _ 60 — 



Deep hole at north point of Nolso, — 100 — 



16 miles E. by S. of south point of Nolso, — So- 

 ft is uncertain whether this species can be allowed to retain its place in the genus Abietinaria. 



16 



Tlie Ingolf-Expedition. V. 7. 



