FORAMINIFERA OF THE ATLANTIC OCEAN 129 



The genera in this family are closely related to and undoubtedly 

 derived from the Anomalinidae. This relationship in the free forms 

 is only seen in the study of the early stages which are mostly attached. 

 From the more complex genera such as Planorbulinella and Linderina, 

 it is but a simple step to the genera of the Orbitoididae. 



The living species are mostly in the Indo-Pacific at the present time, 

 but in the Tertiary were more widely distributed. 



Genus PLANORBULINA d'Orbigny, 1826 



Planorbulina d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 280. — H. B. Brady, 

 Rep. Voy. Challenger, Zoologj^ vol. 9, 1884, p. 655. — Chapman, The Fora- 

 miuifera, 1902, p. 218. — Cushman, Smithsonian Misc. Coll., vol. 77, No. 4, 

 1925, p. 44; Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, p. 326. 



Asterodiscus Ehrenberg, Abhandl. k. Akad. Wiss. Berlin, 1838, p. 130 

 (genoholotype, Asterodiscus forskdlii Ehrenberg). 



Spirobotrys Ehrenberg, Bericht. k. preuss. Akad. Wiss. Berlin, 1844, p. 247 

 (genoholotype, Spirobotrys aegaea Ehrenberg). 



Soldanina Costa, Atti Accad. Pont., vol. 7, fasc. 2, 1856, p. 246 (genoholotype, 

 Soldanina exagona Costa). 



Genotype, by designation. — Planorbulina mediterranensis d'Orbigny. 



Test in the young, coiled, attached by the dorsal surface, very 

 earliest chambers slightly trochoid, closely spiral, later in an irregular 

 series of a single layer about the periphery; wall calcareous, coarsely 

 perforate ; apertures in the early stages one to each chamber, near the 

 periphery or in the irregular chambers sometimes multiple. 



Tertiary and Recent. 



PLANORBULINA MEDITERRANENSIS d'Orbigny 



Plate 24, figures 5-8 



Planorbulina mediterranensis d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 280, 

 No. 2, pi. 14, figs. 4^6; Modeles, No. 79, 1826; Foram. Foss. Bass. Tert. 

 Vienne, 1846, p. 166, pi. 9, figs. 15-17.— H. B. Brady, Rep. Voy. Chal- 

 lenger, Zoology, vol. 9, 1884, p. 656, pi. 92, figs. 1-3.— H. B. Brady, 

 Parker, and Jones, Trans. Zool. Soc, London, vol. 12, 1888, p. 227, 

 pi. 45, fig. 18.— Woodward, The Observer, 1893, p. 176.— Goes, Kongl. 

 Svensk. Vet. Akad. Handl., vol. 25, No. 9, 1894, p. 91, pi. 15, fig. 786; 

 Bull. Mus. Comp. Zool., vol. 29, 1896, p. 73.— Flint, Rep't. U. S. Nat. 

 Mus., 1897 (1899), p. 328, pi. 72, fig. 6.— Cushman, Publ. 311, Carnegie 

 Instit., Washington, 1922, p. 45, pi. 6, figs. 1, 2; Publ. 344, 1926, p. 78. 

 — Heron-Allen and Earland, Journ. Roy. Micr. Soc, 1930, p. 186. 



Test adherent, flattened ; early chambers distinctly spiral, later ones 

 less so, often irregularly annular in their arrangement, more or less 

 lobulated on the ventral face; periphery irregular, often angular; wall 

 very conspicuously perforated ; early chambers usually with a brown- 

 ish color, later chambers grayish-white; sutures depressed, often 

 clearly marked on the dorsal face by a distinct band of shell material; 

 apertures at either side of the chamber in the adult, simple, each with 

 a raised lip. 



Diameter up to 1 mm. 



