FORAMINIFERA OF THE ATLANTIC OCEAN 49 



Subfamily 3. Orbitolitinae 



Test in the early stages planispiral, at least in the microspheric 

 form, later annular, in the simplest forms the chambers only partially 

 divided, completely so in the more complex forms; apertures on the 

 peripheral face. 



Genus PRAESORITES H. Douville, 1902 



Praesoritea H. DotrviLLf;, Bull. Soc. G60I. France, ear. 4, vol. 2, 1902, p. 291. — 

 CusHMAN, Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, p. 221. 



GenoTiolotype. — Praesorites moureti H. Douville. 



Test in the eariy stages planispiral, at least in the microspheric 

 form later annular; chambers in a single plane, not completely 

 divided into chamberlets; apertures numerous. 



Cretaceous. 



Genus SORITES Ehrenberg, 1838 



Sorites Ehrenberg, Abhandl. k. Akad. Wiss. Berlin, 1838, p. 134. — Gush 



MAN, Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, p. 221. 

 Orbitolites (part), of Authors (not Lamarck). 



Genotype, by designation. — Sorites dominicensis Ehrenberg. 



Test discoid, planispiral in the early stages at least of the micro- 

 spheric form, later annular, completely divided into chamberlets; 

 typically in a single layer, those of each annular chamber com- 

 municating with the adjacent ones as with those of the preceding 

 and succeeding annular chambers; wall imperforate except in the 

 very earliest chambers; apertures in a single line along the periphery. 



Miocene to Recent. 



Taramellina Munier-Chalmas is probably a synonym of Sorites. 



Under this genus are included those species which have a single 

 layer of annular chambers divided into chamberlets in the adult 

 often referred to " Orhiculina" and ''Orbitolites." 



SORITES MARGINAUS (Lamarck) 



Plate 18, figures 1-4 



OrbvUtes marginalis Lamarck, Syst. Anim. sans Vert., vol. 2, 1816, p. 196, 

 No. 1. 



Orbitolites marginalis W. B. Carpenter, Phil. Trans., vol. 174, 1883, p. 560, 

 fig. 1; Rep. Voy. Challenger, "Orbitolites," 1883, p. 20, pi. 3, figs. 1-7; pi. 

 4, figs. 1-5. — H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, 

 p. 214, pi. 15, figs. 1-5.— Flint, Ann. Rep't U. S. Nat. Mus., 1897 (1899), 

 p. 304, pi. 50, fig. 2; pi. 51, fig. 1.— Cushman, Bull. 71, U. S. Nat. Mus., 

 pt. 6, 1917, p. 92, pi. 38, figs. 1, 2, text fig. 47. 



Test thin, much compressed, circular in outline in the adult, the 

 whole test composed of a single layer of chambers, each with a single 

 layer of chamberlets throughout, early chambers in a spiral, later 



