iET.6 FORAMINIFERA: POLYMORPHINIDAE — CUSHMAN AND OZAWA 125 



chambers elongated, arranged in a clockwise, sigmoid series, each 

 succeeding chamber much farther removed from the base; sutures not 

 depressed, distinct; wall smooth; aperture radiate. 



Length of holotype 0.90 mm.; breadth 0.45 mm.; thickness 0.20 

 mm. 



Holotype. — (Cushman Coll. No. 11799.) From the Eocene, Mount 

 Moriah beds, yellow sandy clay overlying orbitoidal limestone, 

 Vistabella quarry, Trinidad, British West Indies. 



In general features it is very similar to S. jacksonensis, but the 

 sigmoid arrangement of chambers in the present species is clock- 

 wise, while in S. jacksonensis, it is contraclockwise. We have no 

 specimens of S. jacksonensis having a clockwise arrangement of 

 chambers. The species from Trinidad, although they are represented 

 by but few specimens, are clockwise. Therefore the Trinidad speci- 

 mens are separated from the Jackson species, and the specific name 

 nuttalli is given for Dr. W. L. F. Nuttall who has described many 

 species from Trinidad. 



SIGMOMORPHINA PLINTH (Cushman) 



Plate 32, figures 7 a-c 



Polymorphina flintii Cushman, Bull. 104, U. S. Nat. Mus., pt. 4, 1923, p. 155, 

 pi. 40, fig. 10. 



Test oval or somewhat rhomboidai, compressed, margin more or 

 less angulate; chambers elongated, slightly inflated, arranged in a 

 clockwise, sigmoid series, each succeeding chamber removed farther 

 from the base; sutures distract, but very slightly depressed; wall 

 smooth, thick; aperture radiate. 



Maximum length, 2.50 mm. ; breadth, 1.35 mm. ; thickness, 0.55 mm. 



This is a large well-characterized species in its more or less com- 

 pressed test, consisting of elongated chambers arranged in a clock- 

 wise sigmoid series. 



Distribution. — This species occurs at a large number of Albatross 

 stations off the eastern coast of the United States at depths ranging 

 from 56-72 fathoms. Somewhat similar specimens occur in the 

 upper Pliocene of Natsukawa, Province of Echigo, Japan, and in the 

 Miocene, Janjukian, of Filter quarry, Batesford, Victoria, Australia. 



SIGMOMORPHINA PSEUDOREGULARIS Cushman and Thomas 



Plate 32, figures 8 a-c 



Sigmomorpha (Sigmomorphina) pseudoregularis Cushman and Thomas, Journ. 



Pal., vol. 3, 1929, p. 178, pi. 23, figs. 5 a-c. 

 Polymorphina regularis Stadnichenko (not von Miinster), Journ. Pal., vol. 1, 



1927, p. 231, pi. 38, figs. 18, 19. 



Test large; length about twice the width and thickness a little 

 more than half the width; median longitudinal ridge on both sides 

 with sutures sloping backward, both right and left sets beginning at 



