CRETACEOUS FORAMINIFERA. 33 



Pleurostomella, Bolivina.l 



ventricose and prominent ; the anterior one usually more oblong than the rest, from 

 its anterior part not being embraced, as all the preceding ones, by the next segment. 

 Septal plane convex ; semilunar. Septal orifice single, placed near the umbilical 

 border of the septal plane, and usually characterized by a curious obliquity at its 

 inner part, owing to the two lips of the orifice not meeting at their umbilical 

 extremites, but passing one behind the other. Texture hyaline ; transparent ; when 

 examined after being mounted in Canada balsam, through a high power, it is seen to 

 be perforated by innumerable minute foramina. WILLIAMSON, (Recent Foraminifera 

 Gt. Brit., p. 62.) 



Locality. Meeker county, Minnesota ; Saline county, Nebraska; South Chicago, Illinois. Of the 

 material examined containing this species, in that from Minnesota it was quite rare; from Nebraska very 

 common, and in that from Illinois, rare. It has also been found in the Post-tertiary of Canada. 



PLEUROSTOMELLA, Reuss. 

 PLEUROSTOMELLA SUBNODOSA Reuss. 



PLATE C, FIG. 25. 



Nodosaria nodosa (pars.) REUSS, 1845. Verstein. Bohm. Kreid., pt. 1, p. 28, pi. xiii, fig. 22 (fide Reuss). 

 Dentalina subnodosa (pars.), Id. 1850. Haidinger's Naturw. Abhandl., vol. iv, p. 24. plate i, flg. 9 (fide 



Reuss). 



Pkurostomella subnodosa, Id. 1860. Sitzungsb. d. k. Ak. Wiss. Wien, vol. xl, p. 204, pi. viii, flg. 2, a, b. 

 Pleurostomella subnodosa MARSSON, 1S78. Mittheil. Naturw. Vereine Neu-Vorpom. u. Rilgen, Jahrg. 



x, p. 133. 

 Pleurostomella subnodosa BRADY, 1884. Report on Foram. H. M. S. Challenger, Zool., vol. ix, p. 412, 



figs. 12, 13. 



" D. subnodosa (T. I. f. 9), elongata, subrecta ; loculis fere regulariter incres- 

 centibus, parum convexis, ultimo maximo, convexo, breviter acuto ; primo minimo 

 obtusum-sculo ; apertura nuda. Long.=1.15 mm." REUSS. (Haidinger's Naturw. 

 Abhandl., vol. iv, p, 24, pi. i, fig. 9.) 



Test elongated, nearly straight ; chambers quite regularly increasing, slightly 

 convex, the last one the largest, convex, shortly acute ; the first chamber smallest, 

 rather obtuse ; aperture naked. 



Locality. Saline county, Nebraska ; South Chicago, Illinois. 



BOLIVINA, d'Orbigny. 



BOLIVINA DILATATA EeUSS, 

 PLATE C, FIG. 26. 



Bolivina dilatata REUSS, 1849. Denkschr. d. k. Akad. Wiss. Wien, vol. i, p. 381, pi. xlviii, flg. 15. 

 Bolivina dilatata TERRIGI, 1880. Atti dell' Accad. Pont., ann. xxxiii, p. 197, pi. ii, flg. 42. 

 Bolivina dilatata BRADY, 1884. Report on Foram. H. M. S. Challenger, Zool., vol. ix, p. 418, pi. Hi, 



flgs. 20, 21. 



Bolivina dilatata. "Testa cuneata, superne dilatata, infra acuta, compressa, punc- 



-3 



