FORAMINIFERA OF THE PHILIPPINE AND ADJACENT SEAS. 469 



Genus BILOCULINA d'Orbigny, 1826. 



BILOCULINA DEPRESSA d'Orbigny. 



Plate 96, figs. 2a, h. 



Biloculina depressa d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 298, No. 7. — 

 H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 145, pi. 2, 

 figs. 12, 16, 17; pi. 3, figs. 1, 2.— Cushman, Bull. 71, U. S. Nat. Mus., pt. 6, 

 1917, p. 74, pi. 28, figs. 1, 2. 



This is one of the most common species of the genus, occurring usu- 

 ally in the deeper water, as is 

 shown elsewhere. It has occurred 

 at 44 stations in the material, rang- 

 ing in depth from 78 to 1,560 

 fathoms (143 to 2,853 meters), the 

 average 475 fathoms (869 meters). 

 Bottom temperatures are given at 

 27 stations, rangmg from 36.3° F. 

 to 59.6° F. (2.3° C. to 15.3° C), the 

 average being 48.5° F. (19.1° C). 



Specimens are not common at \ 

 any of the stations. They were 

 found mostly in the deeper water 

 of the Sulu Sea, China Sea, and 

 between the islands; also ui the 

 region to the south, in Sibuko 

 Bay, Borneo; Gulf of Tomini, 

 Celebes; Molucca; between Gillolo 

 and Makyan Island; off Bouro 

 Island; Molucca Sea; Flores 

 Sea; Gulf of Boni; and Macassar 

 Strait. 



This is a common species of deep and cooler waters in all the 



oceans. 



Biloculina depressa — Material examined. 



Figs. 45-47.— Bilocui-ina depressa d'Orbigny. 

 45, aperture of young specimen, with ellip- 

 tical aperture and elongate tooth. x 50. 

 From Albatross station d5236. 46, aper- 

 ture OF A later stage SHOWING TnE GREATER 

 ELONGATION OF THE APERTURE AND TOOTH. 



X 100. From Albatross station d5201. 47, 

 .4perture of an adult with very narrow 

 curved .iperture, largely occupied by the 

 somewhat expanded tooth. x 40. from 

 Albatross station d5236. 



