ROTALIIDAE — DISCORBIS; CYMBALOPORA. 41 



Discorbis subaraucana, new species. 



(Plate 7, Figures 1, 2.) 



Test unequally biconvex, dorsal side somewhat arched, the ventral side 

 very shghtly convex, flattened, or even somewhat concave; periphery not 

 lobulated, composed of about 2.5 coils, 6 to 8 chambers in the last-formed 

 one; sutures oblique, curved, hmbate on the dorsal side, except in the last 

 2 or 3 chambers in the adult, ventrally also somewhat hmbate, especially in 

 the early stages; wall with numerous punctse; aperture at the base of the 

 ventral side of the last-formed chamber, narrow; color of the earher chambers 

 reddish-brown, those of the last-formed ones usually white. 



Diameter up to 0.40 mm. 



The Tortugas material shows a species which is common and 

 which is more like the figures referred by Brady to Discorbis araucana 

 than it is to the originals of d'Orbigny. The figures here given 

 (plate 7, figs. 1 and 2) show the general characters of these specimens. 

 It is the most common in the area and is probably widely distributed 

 in the Pacific and Indian Oceans. 



GenuslCYMBALOPORA Hagenow, 1850. 



Cymbalopora squammosa (d'Orbigny). 



(Plate 6,^Figvires 4 to 6.) 



Rotalia squammosa d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 272, No. 8. 



Rosalina squammosa d'Orbigny, in De la Sagra, Hist. Fis. Pol. Nat. Cuba, 1839, "Forami- 

 niferes," p. 91, pi. 3, figs. 12 to 14. 



Roaalina poeyi d'Orbigny, in De la Sagra, Hist. Fis. Pol. Nat. Cuba, 1839, ' 'Foraminiferes," 

 p. 62, pi. 3, figs. 18 to 20. 



Cymbalopora poeyi Carpenter, Parker, and Jones, Introd. Foram., 1862, p. 215, pi. 13, 

 figs. 10 to 12. — Moebius, Beitr. Meeresfauna Insel Mauritius, 1880, p. 97, pi. 10, 

 figs. 1 to 5.— H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 636, pi. 

 102, figs. 13 a to c. — H. B. Brady, Parker, and Jones, Trans. Zool. Soc. London, 

 vol. 12, 1888, p. 226, pi. 46, fig. 12.— Rhumbler, Zool. Jahrb., Abt. Syst., vol. 24, 

 1S06, p. 71, pi. 5, fig. 59.— Cushman, Bull. 71, U. S. Nat. Mus., pt. 5, 1915, p. 24, 

 pi. 10, fig. 1; pi. 14, fig. 5; fig. 28 (in text). — Heron-Allen and Earland, Trans. 

 Zool. Soc. London, vol. 20, 1915, p. 687. 



Discorbina poeyi Goes, Kongl. Svensk. Vet. Akad. Handl., vol. 19, 1882, No. 4, p. 107, pi. 

 8, figs. 264, 265. 



Test subcorneal, trochoid, dorsal side forming a cone, bluntly pointed, of 

 variable height, ventral side flattened or very shghtly concave, consisting 

 usually of 6 or 7 chambers, of peculiar shape, widest at the outer border, 

 thence contracted, widening again, and finally contracted again, tapering 

 toward the center, where all are united; chambers separated by a definite 

 depressed area; aperture at the margin of the base of the last-formed cham- 

 ber; color of the earher portion reddish-brown, the latter part white. 



Diameter of the Tortugas specimens up to . 75 mm. 



This is one of the common species in the region, occurring at 

 nearly all the stations. It was originally given a name by d'Orbigny 

 in 1826, his specimens coming from Martinique. In 1839 he de- 

 scribed the species under the genus Rosalina, and with it Rosalina 

 poeyi. These have been considered the same species by most 

 authors, but the name poeyi was taken by Carpenter in 1862 and 

 has since been followed. However, according to the rules of priority, 

 the name squammosa used in 1826 by d'Orbigny is not a nomen 



