FORAMINIFERA OF THE ATLANTIC OCEAN. 



65 



This probably represents a Pacific species very closely allied to our 

 West Indian one. 



Valvulina ovicdoiana — material e.vamined. 



Genus CHRYSALIDINA d'Orbigny, 1846. 



Chrysalidina d'Orbigny (type, C. gradata d'Orbigny), For. Foss. Vienne, 1846, 

 p. 194.— H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 387.— 

 Chapman, The Foraminifera, 1902, p. 167.— Cushman, Bull. 71, U. S. Nat. 

 Mu8., pt. 2, 1911, p. 60. 



Description. — Test many chambered, triserial, at least in the 

 early portion, tapering; apertures numerous, scattered over the ter- 

 minal wall of the chamber; other walls also porous. 



Three species of tliis genus are known, the type from the Creta- 

 ceous, another species C. pulchella Cushman, which I described from 

 the Gatun Formation of the Panama Canal Zone, and the recent 

 C. dimorpha H. B. Brady, which is a typically Indo-Pacific species, 

 but which is recorded from the Atlantic. It is quite probable that 

 the Cretaceous species is not generically the same as the last two, 

 but further study is necessary to determine this. 



CHRYSALIDINA DIMORPHA H. B. Brady. 



Plate 19, fig. 4. 



Chrysalidina dimorpha H. B. Brady, Quart. Journ. Micr. Sci., vol. 21, 1881, p. 

 54; Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 388, pi. 46, figs. 20, 21.— 

 Woodward, Journ. New York Micr. Soc, 1885, p. 149.— Egger, Abh. kon. 

 bay. Akad. Wiss. Munchen, Cl. 11, vol. 18, 1893, p. 274, pi. 6, figs. 47, 51, 

 52.— Chapman, Proc. Zool. Soc. London, 1895, p. 20.— Millett, Journ. Roy. 

 Micr. Soc, 1900, p. 12, pi. 1, fig. 14.— Dakin, Rep. Ceylon Pearl-Oyster 

 Fisheries, vol. 5, 1906, p. 233.— Cushman, Bull. 71, U. S. Nat. Mus., pt. 2, 

 1911, p. 60, figs. 96-97 (in text); Bull. 100, U. S. Nat. Mus., vol. 4, 1921, 

 p. 144. 



Description. — Test free, elongate, tapering, triangular in cross sec- 

 tion, the sides nearly equal, somewhat concave, the edges slightly 

 carinate; early portion acute, consisting of chambers arranged tri- 

 serially, the latter portion composed of chambers arranged in a single 

 series; wall hyaline, perforate; apertures numerous on the broadened 

 terminal face of the chamber. 



Length about 0.50 mm., diameter about 0.25 mm. 



