KONGL. SV. VET. AKADEMIENS HANDLINGAK. BAND. 19. N:0 4. 143 



Rhabdammina abyssoruiu Särs. var. robusta n. 



Tab. XII, tigg. 430—431. 



As far as I ain aware of, tlie type form has not been described except in a short no- 

 tice in the last Edit. of Griffiths and Henfrey's Micrograph. Dictionary, and in »Des- 

 cript. Catalogue of objects from Deep-sea dredgings exhibited at the Soirée of the 

 Roy. Microscop. Soc. Kings College 1870, by W. B. Carpenter.» 



Our form has a very brittle test, composed entirely of siliceous sandgrains. Its 

 »body» displays at the roots of its 3 or 4 arms a tendency to swelling, corresponding 

 to the swelling or bulb in the early stage of Hyperammina. The arms radiate in the 

 same plane, tapering gradually at their ends, which are furnished with a central, nar- 

 row and round aperture. 



It is scantily met with in the coi-alline-gravel attaining a length of 16 ram. 



Fig. 430: Three-armed specimen. 



Fig. 431: Four-armed. 



Syn. Rhabdammina abyssorum Särs., 1868, Fortsatte Bemierkniiig. över det dyriske Livs Utbredning i 



Havets Dybder; Christianiu Vid. Selsk. Forhandl. 18G8, p. 248 (nec 

 descripta uec delineata). 



Appenclix. 



Syn. Rliabdamm.ina linearis Bradv, 1879, Retic. Rhizop. Challenger-Exp.; Qnart. Journ. microsc. se. 73, 



p. 37, t. 3, figg. 10—11. 



Jaculella acuta Brady. 



Tab. XII, fig. 432. 



Provisionally I refer our form to this species although not convinced either as 

 to the true nature of these organisms or of their identity. Ours is slender with a 

 very narroAV channel, which here and there exhibits very faintly traces of septa. 



It is not common in the coralline-gravel. 



Syn. Jaculella acuta Brady, 1879, Reticul. Rhizopod. Challenger-Exped.; Quart. Journ. microsc. 



se. 73, p. 'äb, t. 3, figg. 12—13. 



