52 BULLETIN 161, UNITED STATES NATIONAL MUSEUM 



Such specimens occur widely distributed and often are very abun- 

 dant. They occur off Fiji in 40 to 50 fathoms; in 12 to 24 fathoms, 

 off Nairai; in 3 fathoms, Viva Anchorage; 12 fathoms off Levuka; 

 and Mokaujar Anchorage. From other areas the species occurs at 

 Eangiroa; Rutavu; Rotonga; both off the island and from the 

 lagoon at Niau; Port Lotten, Kersail, Caroline Islands; and in 21 

 fathoms, Guam Anchorage, Ladrone Islands. The data for the 

 Albatross stations are given in the accompanying table. 



TRILOCULINA CIRCULARIS Bornemann 



Plate 11, Figukes 11 a-o 



Triloculina oircularis Bobnemann, Zeitschr. deutsch. geol. Ges., vol. 7, p. 349, 

 1855.— Reuss, Sitz. Akad. Wiss. Wien, vol. 48, pt. 1, p. 41, 1863.— Cushman, 

 U. S. Nat. Mus. Bull. 71, pt. 6, p. 67, pi. 25, fig. 4 ; pi. 26, fig. 1, 1917 ; Car- 

 negie Inst. Washington Publ. 213, p. 290, 1918 ; Proc. U. S. Nat. Mus., vol. 

 56, p. 638, 1919 ; U. S. Nat. Mus. Bull. 100, vol. 4, p. 462, pi. 92, figs. 1, 2, 1921 ; 

 Carnegie Inst. Washington Publ. 311, p. 74, 1922. — Hofkeb, Flora en Fauna 

 der Zuiderzee, Protozoa, p. 135, fig. 15 (in text), 1922. — Cushman, Carnegie 

 Inst. Washington Publ. 342, p. 69, pi. 25, figs. 5, 6, 1924; Publ. 344, p. 82, 

 1926. — Hofker, Zoology of the Faroes, vol. 2, pt. a, Foraminifera, p. 7, 

 1930. — Cushman and Valentine, Contr. Dept. Geol. Stanford Univ., vol. 1, 

 no. 1, p. 15, pi. 4, figs. 4 a-c, 1930. (For further references to this species, 

 see Cushman, U. S. Nat. Mus. Bull. 104, pt. 6, p. 58, 1929.) 



Test rounded, compressed, the periphery rounded, the three cham- 

 bers making up the visible portion of the test, rounded, inflated ; last- 

 formed chamber strongly embracing; sutures distinct, depressed; 

 wall smooth, polished; aperture, a narrow crescentiform slit with a 

 large, flattened, semicircular tooth. Length, 0.4-1 mm.; breadth, 

 0.3-1 mm. ; thickness, 0.2-0.35 mm. 



This is one of the commonest species in warm shallow waters, and 

 apparently has a very wide distribution. The general character of a 

 large semicircular platelike tooth nearly filling the large opening is 

 a constant one. The early quinqueloculine stages are usually found 

 accompanying the adult triloculine ones, but are usually of much 

 smaller size. 



The accompanying table gives the distribution of this species as 

 found in our collections at the Albatross stations. In addition it has 

 occurred in shoal water inside the lagoon, Pinaki Atoll; Vavau 

 Anchorage, Tonga Islands, 18 fathoms; and off Nairai, Fiji, in 24 

 fathoms. 



