FORAMINIFERA OF THE NORTH PACIFIC OCEAN. 11 



GLOBIGERINA SACCULIFERA H. B. Brady. 



Plate 2, ligs. 4-6; plate 5; plate 10, fig. 4. 



Globigerina helicina Carpenter, (not G. helicina d'Orbigny), Intr. Foram., 1862, 



pi. 12, fig. 11. 

 Globigerina sacculifera H. B. Brady, Geol. Mag., Dec. 2, vol. 4, 1877, p. 535; 



Quart. Journ. Micr. Sci., vol. 19, 1879, p. 73; Rep. Voy. Challenger, Zoology, 



vol. 9, 1884, p. 604, pi. 80, figs. 11-17; pi. 82, fig. 4.— Egger, Abh. kon. bay. 



Akad. Wiss. Munchen, CI. n, vol. 18, 1893, p. 369, pi. 13, figs. 50, 51.— Goes, 



Bull. Mus. Comp. Zool., vol. 29, 1896, p. 66. — Silvestri, Mem. Pont. Accad. 



Nuovi Lincei, vol. 15, 1899, p. 263, pi. 5, fig. 5.— Flint, Ann. Rep. U. S. 



Nat. Mus., 1897 (1899), p. 322, pi. 70, fig. 1.— Millett, Journ. Roy. Micr. 



Soc, 1903, p. 688.— Bagg, Proc. U. S. Nat. Mus., vol. 34, 1908, p. 154. 



Description. — Test composed of numerous chambers, in. its early 

 stages very similar to G. bulloides but later developing a more oblong 

 form, the chambers extended, somewhat compressed and with acces- 

 sory apertural openings, the final chamber often flattened and irregu- 

 larly formed toward the outer end; wall strongly reticulated in all 

 but the final chamber which is much smoother than the others; aper- 

 ture large, arched with other accessory openings in the chambers of 

 adult specimens. 



Diameter up to and sometimes slightly exceeding 1 mm. 



Distribution.— Brady records this species from three North Pacific 

 Challenger stations, ranging in depth from 345 to 1,850 fathoms. 

 Bagg records it from all but one of the nineteen Albatross stations in 

 the vicinity of the Hawaiian Islands from which he examined material. 

 I have found this species present and often in considerable numbers 

 in material from a very large number of North Pacific stations in the 

 Albatross, Nero, Alert, and Tuscarora material. These stations range 

 in depth from 268 to 2,552 fathoms. 



This species is easily distinguished, especially in its adult form. In 

 some specimens where the accessory apertures are large it is possible 

 to look through the opening between the last chambers and those of 

 the previous whorl. The figured specimen shows the general character 

 of the last chamber, its smoother surface and the accessory apertural 

 openings. 



As noted in regard to the preceding species this species seems to be 

 practically unknown as a fossil form. By its large openings it is 

 one of the highest developed species of the genus. 



The last-formed chamber in adults is often very variable in shape,. 

 especially the outer border, which is often deeply lobed and irregularly 

 extended. 



6912°— 14 2 



