FORAMTNIFERA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 135 



Haploph/ragmoides umbilicatum was found in abundance in the deposit from 

 Station 420, 2620 fathoms, glacial mud, but not from any other. 



Genus CRIBROSTOMOIDES, Cushman. 



Cribrostomoides bmdyi, Cushman. 

 (Haplophraymium latidorsatum (Bornemann)). 



Obtained from Stations 313, 418, 420, 459, and 467 (rare). One of the commonest 

 of arenaceous deep-sea Foraminifera. Range, from Franz Josef Land to the Antarctic 

 Continent, and in all oceans, at depths of from 113 to 3950 fathoms. 



Genus CYCLAMMINA, H. B. Brady. 



Cyclammina cancellata, H. B. Brady. 



Good specimens of this species, the largest of its genus, with its wonderful 

 labyrinthine structure, the function of which has yet to be discovered, were obtained, 

 but rarely, at Stations 420 and 447. North and South Atlantic and Pacific Oceans, 

 75 to 2900 fathoms. 



Cyclammina pusilla, H. B. Brady. 



This handsome little species has been found at seven stations, viz. 300, 313, 338, 

 416, 417, 420, and 447, but nowhere common. Not known, so far as I am aware, from 

 the North Atlantic, and from bub one station in the South Atlantic and one in the 

 Antarctic (Challenger}. Common in the Pacific (CUSHMAN). 93 to 2879 fathoms. 



Cyclammina contorta, sp. nov. (Plate II. figs. 5-7.) 



Test nautiloid, compressed, slightly urnbilicate, convex towards the peripheral edge ; 

 composed of from three to four convolutions, the last two completely enveloping the 

 others ; segments numerous, usually fifteen in number. Walls of test finely arenaceous, 

 and thin externally; body of walls and throughout the labyrinthine structure with 

 larger angular mineral particles incorporated. The chambers of the first convolution 

 and the earlier ones of the second are thin-walled and but slightly labyrinthine : all the 

 succeeding chambers become partly labyrinthine, and the last three or four completely 

 so (Plate II. fig. 7). Suture lines slightly depressed and contorted anteriorly ; exterior 

 smooth, slightly iridescent ; imperforate in the perfect state, but when the outer wall is 

 rubbed or broken away the open tubules of the labyrinthine communications with the 

 main chambers become exposed to view ; aperture usually a curved slit, but in some 

 specimens this is altered into three or more circular openings or pores situated at the 

 base of the apertural face. 



Colour vandyke brown near the area of the umbilicus, becoming much lighter at the 

 periphery ; suture lines very dark, almost black. 



Diameter, 2 '5 to 4 '2 mm. 



(ROY. soc. EDIN. TRANS., VOL. XLIX., 1009.) 



