54 BULLETIN 161, UNITED STATES NATIONAL MUSEUM 



nally described. Specimens less well developed but having the char- 

 acteristic early stages and showing slight tendencies of becoming 

 uniserial were found at Viva Anchorage, 3 fathoms, and Rotonga, 

 7 fathoms. 



This species is a unique one, although from the records it is prob- 

 ably to be looked for as widely distributed in the Indo-Pacific region 

 in shallow water. It represents the only attempt of this group, 

 represented typically by Elphidium, to assume an uncoiled form, and 

 is evidently a very recent development in the history of this family. 



Family CAMERINIDAE 

 Subfamily Camerininae 



Genus OPERCULINELLA Yabe. 1918 



Operculinella Yabe, Sci. Rep. Tohoku Univ., ser. 2 (GeoL), vol. 4, p. 126, 1918. 

 Synonyms: Amphistegina W. B. Carpenter, 1859 (not d'Orbigny); Nummulites 

 H. B. Brady, 1884 (not Lamarck). 



Genoholotype. — Amphistegina cumingii W. B. Carpenter. 



Test lenticular and involute in the young, bilaterally symmetrical, 

 in the adult with a broadly flaring complanate border; chambers 

 simple; aperture at the base of the apertural face, median. Late 

 Tertiary and Recent. 



OPERCULINELLA VENOSA (Fichtel and Moll) 



Plate 18, Figures 2-6 



Nautilus venosus Fichtel and Moll, Test. Micr., p. 59, pi. 8, figs, e-h, 1798. 



Nummulites venosa Chapman, Proc. Zool. Soc. London, 1895, p. 47. 



Operculina venosa Chapman, Proc. Roy. Soc. Victoria, vol. 26, p. 173, 1913. — 

 CusHMAN, U. S. Nat. Mus. BuU. 100, vol. 4, p. 383, 1921. 



Amphistegina cumingii Carpenter, Philos. Trans., 1859, p. 32, pi. 5, figs. 13-17. 



Nummulites cumingii H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 

 p. 749, pi. 112, figs. 11-13; woodcut, fig. 22, 1884.— Cushman, U. S. Nat. 

 Mus. Bull. 71, pt. 4, p. 39, pi. 14, fig. 6, 1914.— Heron-Allen and Ear- 

 land, Trans. Zool. Soc. London, vol. 20, p. 739, 1915. 



Operculinella cumingii Yabe, Sci. Rep. Tohoku Imp. Univ., ser. 2 (GeoL), vol. 4, 

 p. 126, pi. 17, figs. 8-12, 1918. 



Operculinella venosa Cushman, Carnegie Inst. Washington Publ. 342, p. 50, 

 pi. 17, fig. 7, 1924. 



Test free, involute, biconvex, early portion thick, later portion 

 making a wide, thin flange about the central portion; sutures fairly 

 distinct; supplementary canal system well developed; edge of test 

 carinate in the flangelike portion. 



The only specimens which can be referred to this species in the 

 present collections are from off Levuka, Fiji, in 12 fathoms, and at 

 Vavau Anchorage, Tonga Islands, in 18 fathoms. This form is 

 rather common at both these localities, but none of the specimens 

 are fully developed, and they do not seem quite typical. It is widely 



