TROPICAL. PACIFIC FORAMINIFERA OF ALBATROSS 

 Table 24. — Spiropthalmidium acutimargo — material examined 



71 



Genus PLANISPIRINA Seguenza, 1880 



Planispirina Seguenza, Atti R. Accad. Lincei, ser. 3, vol. 6, p. 310, 1880. — H. B. 

 Beady, Rep. Voy. Challenger, Zoology, vol. 9, p. 193 (in part), 1884. — 

 Chapman, The Foraminifera, p. 9S, 1902. — Cushman, Cushrnan Lab. Foram. 

 Res. Spec. Publ. No. 1, p. 166, 1928 ; U. S. Nat. Mus. Bull. 104, pt. 6, p. 93, 

 1929. 



Genotype. — By designation, Planispirina communis Seguenza. 



Test in the early stages like C'ornuspira, later divided into cham- 

 bers, several to a coil ; aperture simple, without a tooth. 



There are two species of this genus in our Pacific material, only 

 one of which is at all common. 



PLANISPIRINA EXIGUA <H. B. Brady) 



Plate 16, Figures 1 a, o 



Hauerina exigua H. B. Brady, Quart. Journ. Micr. Sei., vol. 19, p. 53, 1879. 



Planispirina exigua H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, p. 196, 

 pi. 12, figs. 1-i ; text-fig. 5b, 18S4.— H. B. Brady, Parker, and Jones, Trans. 

 Zool. Soc. London, vol. 12, p. 216, pi. 40, fig. 4, 18SS — Howchin, Trans. 

 Proc. Roy. Soc. South Australia, vol. 12, p. 5, 1S89. — Egger, Abh. kon. bay. 

 Akad. Wiss. Miinchen, CI. II, vol. 18, p. 245, pi. 3, figs. 11, 12, 1893.— 

 Woodward, The Observer, vol. 4, p. 77, 1893. — Millett, Journ. Roy. Micr. 

 Soc, p. 611, pi. 13, fig. 13, 1898.— Chapman, Journ. Linn. Soc. Zool., vol. 30, 

 p. 21, pi. 2, fig. 43, 1907 ; Subantarctic Islands of New Zealand, p. 323, 1909 — 

 Heron-Allen and Earland, Trans. Zool. Soc. London, vol. 20, p. 590, 1915. — 

 Chapman, Biol. Res. Endeavour, vol. 3, pt. 1, p. 11, 1915. — Cushman, U. S. 

 Nat. Mus. Bull. 71, pt. 6, p. 9, fig. 7 (in text), 1917. — Heron-Allen and 

 Earland, Journ. Roy. Micr. Soc, p. 133, 1924. — Cushman, U. S. Nat. Mus. 

 Bull. 104, pt. 6, p. 94, 1929. 



Test much compressed, planispiral, the early whorls undivided, 

 later ones showing usually two or three chambers to the coil, rather 

 indistinct except when the specimens are wet; sutures rather indis- 

 tinct except those of the last-formed coil ; wall fairly smooth, usually 

 opaque ; aperture a narrow elongate opening without a definite tooth. 

 Diameter, 0.3 mm. ; thickness, 0.03-0.05 mm. 



