30 0. NORDGAARD. L^ND ARC. EXP. FRAM 



Gen. Rhamphostomella, Lorens. 



57. Rhamphostomella sca,bra,, Fabr. 



Syn. BiDENKAP Kat., p. 31. 



.July 8, 1901, Ren Bay. 



While Rhamphostomella costata was of common occurence among 

 the specimens from the 2nd Fram Expedition, scabra appeared there 

 from only one locality. The two species are distinguishable from one 

 another by the different size of the avicularia, and still more by the 

 fact that costata has a median oral denticle, while seabra is without 

 one. The puncturing on the back of the colony in scabra, which I 

 have drawn in „Hydr. Biol. Inv. Norw. Fj.", Pi. 5, fig. 10, seems to be 

 a very variable character, and the direction of the ribs cannot serve 

 either, as a distinguishing mark between the two species, as some of 

 the ribs in costata too, may continue on to the prominence below the 

 proximal oral margin. In R. scabra from Ren Bay, the zocecia were 

 0,9 mm. in length and 0,5 mm. in width. 



58. Rhamphostomella, costata, Lorenz. 



Syn. RiDENKAP Kal, p. 31. 



July 22, 1900, the winter haven, about 30 fath.; Sept. 19, 1900, off 

 Forvisnings Valley, 2 — 20 fath., on algse and hydroids; Sept. 20, 1900, 

 the head of Gaase Fjord, 3—20 fath.; June 28, 1901, the mouth of 

 Hvalros Fjord, on Halecium muricatum^; July 8, 1901, Ren Bay, on 

 algffi; July 12, 1901, bay near Land's End; July 19, 1901, the lower 

 part of Gaase Fjord. 



The average length of the zocecia was from 0,8 to 0,9 mm., and 

 their breadth 0,4 mm. In the colonies from Ren Bay, some of the 

 zocecia were furnished with large vicarious avicularia, some of which 

 stood parallel with the longitudinal direction of the zocecia, some per- 

 pendicular to, or forming an acute angle with it. The species appears 

 to be common in the west arctic region, and it has also been found on 

 Jan Mayen, in the north of Norway, Spitsbergen and Franz Josef Land. 



59. Rhamphostomella plicata, Smitt. 



PI. IV, figs. 49 & 50. 



1867. Cellepora plicata (part), Smitt, Ofv. Kgl. Vet. Akad. F5rh. (Appendix), pp. 

 30 & 18i, pi. 28, figs. 189 & 190. 



Determined by Hj. Broch. 



