256 BUULETIN 100, UNITED STATES NATIONAL. MUSEUM. 



Marginulina striatula — Material examined. 



MARGINULINA COSTATA (Batsch). 



Plate 41, figs. 5-8. 



Nautilus (Orthoceras) costatus Batsch, Conch, dea Seesandes, 1791, p. 2, pi. 1, 

 figs. 1 a-g. 



Margimdina costaia H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, 

 p. 528, pi. 65, figs. 10-13. — Sherborn and Chapman, Journ. Roy. Micr. Soc, 

 1889, p. 487, pi. 11, fig. 28.— Terrigi, Mem. R. Com. Geol. Italia, vol. 4, 1891, 

 p. 92, pi. 3, fig. 4. — FoRNAsiNi, Mem. R. Accad. Sci. Istit. Bologna, ser. 5, vol. 3, 

 1893, p. 434, pi. 2, fig. 6; ser. 5, vol. 4, 1894, pp. 213, 214, 217, pi. 2, figs. 18-21.— 

 Jones, Pal. Soc, 1896, p. 235, pi. 1, fig. 21.— Silvestri, Mem. Pont. Accad. 

 Nuovi Lincei, vol. 12, 1896, p. 200, pi. 1, fig. 9; vol. 17, 1900, p. 273, pi. 6, 

 fig. 22.— MiLLETT (part), Journ. Roy. Micr. Soc, 1902, p. 526 (not pi. 11, fig. 20). 



Marginulina raphanus d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 258, No. 1, pi. 

 10, figs. 7, 8; ModMes, 1826, No. 6. 



Description. — Test elongate, subcylindrical, somewhat tapering, 

 early chambers at least in the microspheric form in a partial coil, 

 later ones uniserial and Nodosaria-like, chambers of early portion 

 short and broad, later becoming comparatively longer; wall orna- 

 mented with 15 to 25 raised costae running lengthwise of the test. 



Length up to 4 mm. 



Distrihvtion. — Typical material of this species was found in abun- 

 dance in material from Albatross station D5178, in 78 fathoms (143 

 meters), off Romblon; and at D5277, 80 fathoms (146 meters), China 

 Sea, off southern Luzon, bottom temperature 58.6° F. (14.7° C). 



In the large series obtained both microspheric and megalospheric 

 specimens were present in considerable numbers, the latter pre- 

 dominating, as is usual where both forms are found together in 

 quantity. In the microspheric form the early chambers are dis- 

 tinctly coiled, and in the uncoiling the oblique sutures can be traced 

 for some considerable distance before sutures are developed at right 

 angles to the axis of growth. In the megalospheric form various 

 gradations are seen to the complete Nodosarian condition. Various 

 stages are here shown in both the microspheric and megalospheric 

 forms. This series is especially interesting in showing the relation 

 between Nodosaria and Marginulina, as well as suggesting that a 

 similar relation may be suspected between some of the oblique-sutured 

 species of Nodosaria and certain similar uncoiled forms of Cristellaria. 



