Foraminifera 5M 
Species oF FORAMINIFERA OBTAINED BY THE CANADIAN ARcTIC EXPEDITION. 
Hyperammina subnodosa H. B. Brady. 
(See Plate I, figures 1, 2.) 
para as oo G. M. Dawson, Ann. Mag. Nat. Hist., ser. 4, vol. 7, 1871, 
_ p. 86 fig. 7. 
Hyperammina subnodosa H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 
1884, p. 259, pl. 23, figs. 11-14—Awerinzew, Mem. Acad. Imp. Sci. St. 
Petersburg, ser. 8, vol. 29, No. 3, 1911, p. 12.—Cushman, Bull. 104, U. 8. 
Nat. Mus., pt. 1, 1918, p. 76, pl. 29, figs. 7, 8. 
Specimens are abundant from station 43a, and occur at.43b. The largest 
specimen measures 22 mm. in length, which seems to be a record for the species. 
The proloculum is well marked, usually slightly greater in diameter than the 
remainder of the test. The constrictions are well marked and numerous. The 
wall is composed of rather fine sand grains of nearly uniform size light reddish 
brown in colour, the apertural end much constricted in perfect specimens, the 
aperture itself a small, simple, irregularly rounded opening. The tubes usually 
have specimens of Tholosina bulla attached to the exterior. 
The finding of this species in abundance is especially interesting, as it is one 
of the species not found by Kiaer in the material collected by the Fram in the 
second Norwegian Expedition, in the region to the north of that in which the 
Canadian Arctic Expedition material was collected. Awerinzew in his work 
has considered H. subnodosa as one of the most characteristic species of the 
Arctic. Along the Arctic coast of Siberia it is one of the commonest species. 
Schlumberger recorded it from the cold water of the Okhotsk sea, and I have 
had it from the same locality. Brady in the Challenger report mentions that 
some of the finest specimens he had were from the coast of Greenland. In the 
Atlantic I have found the species very abundant in very cold water, with bottom 
temperatures below the freezing point, north of the Grand Banks of Newfound- 
land. Pearcey records it from the Antarctic, and it is known from deep cold 
waters in various parts of the ocean basins. 
Tholosina bulla (H. B. Brady.) 
(Plate I, figures 1, 2.) 
Placopsilina bulla H. B. Brady, Quart. Journ. Micros. Sci., vol. 21, 1881, p. 51: 
3 Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 315, pl. 35, figs. 16, 17. 
Tholosina bulla Rhumbler, Nachr. Kénigl. Ges. Wiss. Géttingen, 1895, p. 82.— 
Kiaer, Norske Nordhavs Expedition, No. 25, 1899, p. 4.—Cushman, 
Bull. 104, U.S. Nat. Mus., pt. 1, 1918, p. 63, pl. 25, fig. 6. 
Specimens are numerous at stations 43a and 43b attached to the outside 
of the tubes of Hyperammina subnodosa, sometimes six or more being attached 
to asingle tube. The walls of 7. bulla are made up of much finer material than 
the tubes to which they are attached, showing a definite selective power of the 
organism, usually of whitish grains, in decided contrast to the darker red colour 
of the Hyperammina tubes. Near the edge are numerous acerose sponge spi- 
cules. On the outside, especially near the top, are larger fragments of pebbles 
or other foraminifera tests. These occur especially on the outside of the largest 
- specimens. In general, the longest diameter is in the direction of the long axis 
of the tube to which it is attached. The wall is fairly thick, and of nearly 
uniform texture, except for the points noted. A thin film of light-coloured 
material covers the attachment, as a floor to the chamber. 
