CRETACEOUS FORAMINIFERA. 43 



Orbulina.l 



ORBULINA, d'Orbigny. 

 OBBULINA UNI VERSA d'Orbigny. 



PLATE D. FIGS. 23-27. 



"Polymorpha sphasruk vitrece," SOLDANI, 1791. Testaceographia, vol. i, pt. 2, p. 116, pi. cxix, flgs. I-N. 



Orbulina universa d' ORBIGNY, 1839. Foram. Cuba, p. 3, pi. i, flg 1. 



Orbulina universa, Id., 1839. Foram. Canaries, p. 122, pi. i, flg. 1. 



Miliola (Monocystis) cwceMaEriHENBERG, 1854. Mikrogeologie, pi. xxx, flg. 1. 



Miliola sphtxrula, Id., Ibid., pi. xxxi, flg. 1, a, b, c. 



Orbulina granulata var. atra COSTA, 1856. Atti dell' Accad. Pont., vol. vii, p. 116. pi. xi, flg. 2. 



Orbulina granulata var. areolata, Id., Ibid., p. 117, pi. xi, flg. 4. 



Orbulina universa, Id., Ibid., p. 114, pi. xi, flg. 5. 



Orbulina universa WILLIAMSON, 1858. Rec. Foram. Gt. Br., p. 2, pi. 1, flg. 4. 



Orbulina universa POUKTALES, 1858. Amer. Jour. Sci., ser. 2, vol. xxvi, p. 96. 



Orbulina universa BRADY, 1859. Quart. Journ. Micr. Soc., vol. xix, n. s., p. 75. 



Orbulina punctata TEKQUEM, 1862. Foram. du Lias, 2'<"" mem., p, 432, pi. v, flg. 5. 



Globigerina (Orbulina) universa OWEN, 1867. Journal Linn. Soc. Lond., vol. ix, Zool., p. 149, pi. v, flg. 1. 



Globiyerina (Orbulina) continens, Id., Ibid., flgs. 3, 4. 



Globigerina (Orbulina) acerosa, Id., Ibid., flg. 2. 



Orbulina universa STOHR, 1876. Boll. R. Com. Geol. D' Ital., p. 463. 



Orbulina universa SCHWAGKR, 1877. Boll. R. Com. Geol. D' Ital., p. 20, pi. flg. 45. 



Orbulina universa HILGARD and HOPKINS, 1878. Rec. of the Alluvial Basin of the Mississippi river, 



pp. 13, 39, pi. ii, flg. 73. 



Orbulina universa SCHACKO, 1883. Wiegmann's Archiv fur Natur., Jahrg. xlix, p. 428, pi. xiii, flg. 1. 

 Orbulina universa SCHLUMBERGER, 1884. C. R. vol. icviii, pp. 1002-1004, flgs. 1, 2. 

 Otbulina universa BRADY, 1884. Report on Foram., H. M. S. Challenger, Zool., vol. ix., p. 608, pis. 



Ixxviii; Ixxxi, flgs. 8-26 ; pi. Ixxxii, flg. 1-3. 

 Orbulina universa WOODWARD and THOMAS, 1885. Thirteenth Annual Report, Geol. Nat. Hist. Surv. 



Minn., pp. 174, 175, pi. iv, flgs. 25-31. 



Generic character. Shell free, regular, spherical, hollow ; perforated by innum- 

 erable very minute foramina, visible only under a high magnifying power ; septal 

 orifice single, small, situate at some point on the periphery of the shell ; without 

 any marginal projection ; often invisible. 



Specific character. " Spherical ; parietes minutely granular, of a pale grayish- 

 yellow hue. Texture finely arenaceous.* Septal aperture small, normally round, 

 but usually irregular, and sometimes entirely closed up by the inspissated gelatinous 

 sarcode, so as to be invisible. Diam. T V"*V inch."** 



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

 In Minnesota it is common, in Nebraska and South Chicago rare. This species was found in the Post- 

 pliocene by Prof. Eugene W. Hilgard and Dr. F. V. Hopkins, in their " investigation of the microscopic 

 character of the strata of dark-colored, brown or blue clays occurring in the borings of the blue 'delta clay' 

 which is found almost everywhere in the delta coast region of Louisiana and Mississippi. "t It is a very 

 common species. 



*We find by further examination, that the texture is not finely arenaceous, as stated in the description, but calcareous 

 ;i ml similar in every respect to its closely allied species Gtobigcrina bulloides. 

 ""Williamson's Recent Fonuainifera G. B., 1857. 

 Reclamation of the Alluvial Basin of the Mississippi River, p. 12, 1878. 



