72 BULLETIN 161, UNITED STATES NATIONAL MUSEUM 



Globorotalia tumida (Brady). — Bradshaw, 1959, Contr. Cushman Found. 

 Foram. Res., vol. 10, p. 47, pi. 8, figs. 9, 13. 



This cosmopolitan species is one of the most widely represented and 

 most abundant of the planktonics in the deeper-water samples of the 

 present material. 



Its thick, rather heavy-walled test is also distinctive in being 

 dorsally bulging and somewhat elongated in the direction of the 

 last-formed chamber. The test is thick in the center, rounded around 

 the periphery of the early part of the final whorl, but compressed to a 

 blunt bladelike edge around the final one or two chambers. The dorsal 

 sutures are curved, slightly depressed, and usually indistinct ; on some 

 specimens they are scarcely visible. The ventral sutures usually are 

 incised deeply, particularly at their inner ends. The periphery is 

 edged by a thick and heavy linibate keel. The aperture is protected 

 normally by a rather prominent tonguelike projection extending 

 forward (in the direction of coiling) above it. The surface of the wall 

 has a characteristic sugary texture, rarely smooth and polished or 

 translucent as in Globorotalia menardii. The sugary texture increases 

 in graininess toward the umbilical area, where the wall seems to be 

 actually ornamented by a dense concentration of short pillars and 

 blunt spines. 



GLOBOROTALIA TRUNCATULINOIDES (d'Orbigny) 



Plate 27, Figure 7 



Rotalina truncatulinoides d'Orbigny, 1839, in Barker-Webb and Berthelot, 



Hist. Nat. lies Canaries, Paris, vol. 2, pt. 2, Foraminiferes, p. 132, pi. 2, 



figs. 25-27. 

 Globorotalia truncatulinoides (d'Orbigny). — Cushman, 1941, Amer. Journ. Sci., 



vol. 239, pi. 4, fig. 1.— Bolli, Loeblich, and Tappan, 1957, U.S. Nat. Mus. 



Bull. 215, p. 41, pi. 10, fig. 3.— Bradshaw, 1959, Contr. Cushman FouDd. 



Foram. Res., vol. 10, p. 44, pi. 8, figs. 7, 8. 



This cosmopolitan species is found rarely and in only a few samples 

 of the present material. Its occurrence suggests the possibility of 

 local restriction in the southeastern Pacific. Most of the specimens 

 are found in samples from west of the Tuamotu Archipelago ; the species 

 is almost unknown from areas covered by the remaining samples. 



Its distinguishing characteristics are the smoothly rounded, not 

 angled, outline of the test and its high conical form with open umbilicus. 

 Its wall is generally less coarsely rugose than that of Globorotalia 

 punctulata, with which it might be confused. 



