26 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I48 



winter traverse the white forms predominated, accounting for over 

 50 percent of this species. The winter-colored specimens included only 

 shades of pink, and bright red forms were lacking. In the fall and 

 spring traverses the colors were intermediate between summer and 

 winter. 



Distribution, — Overall, Glohigerinoides ruber is the most abundant 

 species of Globigerinoides in the traverses studied. It was also one 

 of the dominant species of the subtropical assemblages. The highest 

 frequency recorded was 43 percent at the summer slope station HH. 

 Along with other species of Globigerinoides, the frequency dropped 

 considerably in the winter, reaching a maximum of only 8 percent 

 (station II). 



GLOBIGERINOIDES ELONGATUS (d'Orbigny) 

 Plate 9, figure 5 



Globigerina elongata d'Orbigiiy, 1826, Banner and Blow, 1960, Coiitr. Cushman 

 Found. Foram. Res., vol. 11, pt. 1, p. 12, pi. 3, figs. lOa-c. 



This species closely resembles and may turn out to be a variant 

 form of Globigerinoides ruber. However, the test is more compact 

 than in G. ruber, and the final chambers are compressed, almost 

 flattened, as in G. conglobatus. 



The primary aperture is symmetrically located above the two earlier 

 chambers in G. elongatus but is less broad than in G. ruber. The 

 present specimens agree with the lectotype of G. elongatus as figured 

 by Banner and Blow. 



Distribution. — This species is rare and was recorded only from 

 Sargasso Sea stations. In all cases the frequencies were less than 1 

 percent. 



GLOBIGERINOIDES TRILOBUS TRILOBUS (Reuss) 

 Plate 9, figures 1-3 



Globigerina triloba Reuss, 1850, Deiikr. K. Akad. Wiss. Wien, vol. 1, p. 374, 



pi. 47, fig. 11. 

 Globigerinoides sacculijer (Brady, 1877), Be, 1959, Micropaleontol., vol. 5, pi. 2, 



figs. 13-15. 



In this species the final chamber is set above the two preceding ones, 

 as in Globigerinoides ruber. However, the coiling of G. trilobus 

 trilobus is essentially trochospiral, and the final chamber does not 

 completely cover the umbilicus, so that the primary aperture is a 

 narrow slit at the base of the chamber. On the dorsal side of the 



