FORAMINIFERA OF THE ATLANTIC OCEAN. 



67 



Genus CRITHIONINA Goes, 1894. 



CritJiionina Goes (type, C. mamilla Goes) Kongl. Svensk. Vet. Akad. Handl., 

 vol. 25, No. 9, 1894, p. 14; Bull. Mus. Comp. Zool., vol. 29, 1896, p. 24.— 

 Rhumblek. Arch. Prot., vol. 3, 1903, p. 229.— Cushman, Bull. 71, U. S. Nat. 

 Mus., pt. 1, 1910, p. 53. — Heron-Allen and Earland, Trans. Linn. Soc. 

 London, vol. 11, pt. 13, 1916, p. 219. 



Description. — Test spherical, lenticular or variously shaped, inte- 

 rior either labyrinthic or with a single chamber, apertures small and 

 scattered or indistinct, wall thick, composed of sponge spicules or 

 very fine sand, often chalky in appearance. 



The especial development of this genus seems to be in the colder 

 waters, especially in the North Atlantic, where in the colder waters 

 it occurs in immense numbers. There are several species. 



CRITHIONINA MAMILLA Goes. 



Plate 27, figs. 1, 2; plate 28, fig. 12. 



Crithionina mamilla Goes, Kongl. Svensk. Vet-Akad. Handl., vol. 25, No. 9, 

 1894. p. 15, pi. 3, figs. 34-36.— ScHAUDiNN, Bergens Mus. Aarbog, 1894-95 

 (1896) No. 9, p. 4.— MiLLETT, Joum. Roy. Micr. Soc, 1899, p. 250, pi. 4. fig. 2.~ 

 Rhumbler, Arch. Prot., vol. 3, 1903, p. 230, fig. 56 (in text). — Heron- 

 Allen and Earland, Journ. Roy. Micr. Soc, 1913, p. 9, pi. 3; Proc Roy. 

 Irish Acad., vol. 31, pt. 64, 1913, p, 40; Trans. Zool. Soc. London, vol. 20, 

 1915. p. 616; Trans. Linn. Soc. Loudon, vol. 11, pt. 13, 1916, p. 219. 



Description. — Test free or attached, comparatively large, very thick 

 walled, central chamber small, connected with the surface by irregular 

 channels; wall composed of fine sandy material, loosely agglutinated, 

 very thick, surface irregular but fairly smooth, interior more granular; 

 apertures small and inconspicuous; color a dirty gray; outer surface 

 often cracked in drying. 



Diameter, up to 4 mm. 



Disirihution. — Goes originally described this species from the 

 Skagerack in 106 meters attached to dead eelgrass, Zostera. Schau- 

 dinn records it from off Bergen, Norway. Heron-iUlen and Earland 

 record it from a large number of stations in the North Sea, Faroe 

 Channel, and also in the Clare Island region and west of Scotland. 

 It is a very common species along our coast from the Newfoundland 

 Banks southward to Cape Hatteras. 



Crithionina mamilla — material examined. 



Locality. 



Depth 



in 

 fath- 

 oms. 



40 16 50 N.; 67 05 15 W. 1,290 



39 22 20 N.; 70 52 20 W. 1.451 



37 38 40 N.; 73 16 SOW. 1,423 



40 01 45 N.; 70 24 00 W. ! 131 

 40 09 30 N.; 67 09 00 W. \ 1,356 



38 29 30 N,; 70 57 00 W. 1,631 



Bot- 

 tom 

 tem- 

 pera- 

 ture. 



o p 



40 



37.5 



37.7 



47.7 

 37.8 



Character of 

 bottom. 



bu. m. s 



sy.oz 



glob, oz 



gn. s. bic.sp, 

 gy. Rlob. oz. 

 br. oz. for.., 



Abundance. 



Common, 



Few. 



Common. 



Few. 



Common. 



Few. 



