ART. IC THE rOBAMINIFEEA GEKUS EHRENBERGINA CUSHMAN / 



EHRENBERGINA PUPA (d'Orbigny) 



Plate 2, figs. 5, 6 



Cassidulina pupa d'OnBiGNY, Foram. Amer. Merid., 1839, p. 57, pi. 7, figs. 21-23. 



Ehrenbergina pupa H. B. Bkady, Rep. Voy. Challenger, Zoologj-, vol. 9, 1884, p. 

 433, pi. 55, fig.s. la, h; pi. 113, figs. lOa-c. — Chapman Journ. Linn. Soc. Zool., 

 vol. 30, 1910, p. 406.— Pearcey, Trans. Roy. Soc. Edinburgh, vol. 49, 1914, 

 p. 1016. — Chapman. Rep't. British Antarctic Exped., Geol., vol. 2, 1916 

 (1917), p. 31, pi. 2, figs. 15a, 6.— Cushman, Bull. 104, U. S. Nat. Mas., pt. 3, 

 1922, p. 137. 



Test sub triangular, broader at the apertural end, bluntly pointed 

 at the initial end, composed of comparativel}^ few chambers, on the 

 dorsal side smooth and rounded, the ventral side with a slight longi- 

 tudinal depression; chambers inflated, distinct, wall fairly thin, finely 

 punctate, smooth; sutures distinct, depressed, especiall}' on the ven- 

 tral side, not forming either spines or ridges; aperture elongate, 

 curved, nearly at right angles to the edge of the chamber. 



Length 0.35 mm. 



D'Orbigny 's types were from the Falkland Islands. There are 

 rather wide spread records for the species but mostly from the South 

 Atlantic and South Pacific. 



It is very distinct from all the other species of the genus in its 

 ver}^ smooth rounded test with the absence of all ornamentation. 

 Egger's figures^ do not at all correspond with the chai-acters of 

 this species. It may be noted that the original figures of d'Orbigny 

 show a more compressed form than do later figures. 



Chapman" refers specimens from the Lower Cretaceous to this 

 species. There are, however, numerous points in which his figure 

 does not fit well with what is known of E. pupa and it is to be ques- 

 tioned if it really represents an Ehrenbergina. 



Chapman has recently referred " Upper Eocene specimens from New 

 Zealand to this species. The figured specimen is not elear in all its 

 details but hardly seems referable to this species as developed in the 

 present ocean. 



A further study with a larger suite of specimens of the form that 

 I have referred to E. glabraia from the Byram Marl of Mississippi' 

 shows it to belong to the peculiar group of Gaudryina in wliich there 

 is a slight basal triangular portion followed by a later development 

 in which as in Ehrenbergina there is developed a dorsal side that is 

 flattened and a ventral one with deeply depressed sutures. 



».4.bhandl. kon. bay. Akad. Wiss. Munchen, CI. II. vol. 18, 1893, pi. 7, figs. 4.3-46. 

 •Quart. Journ. Geo?. Soc, vol. 50, 1894, p. 304, pi. 34, ttgs. 6a, h. 

 ■New Zealand Geol. Surv., Pal. Bull. No. 11, 1926, p. 43, pi. 9, fig. 15. 

 « U. S. Geol. Survey Prof. Paper 129-E, 1022, p. 93, pi. 17, figs. 4a-c. 



