MILIOLIDAE — TRILOCULINA; BILOCULINA. 77 



Triloculina labiosa d'Orbigny. 

 (Plate 12, Figure 1.) 



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

 niferes," p. 157, pi. 10, figs. 12 to 14.— Cushman, Bull. 71, U. S. Nat. Mua., pt. 6, 

 1917, p. 70; Proc. U. S. Nat. Mus., vol. 59, 1921, p. 70, pi. 16, figs. 13, 14. 



Miliolina labiosa H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 170, pi. G, 

 figs. 3 to 5. 



Test much broader than long; surface largely composed of the two last- 

 formed chambers; chambers often somewhat irregular; periphery rounded; 

 surface smooth, but dull; aperture crescentiform, with a somewhat triangular 

 tooth, placed somewhat back from the aperture. 



Diameter of the Tortugas specimens up to 0.60 mm. 



Specimens agree very closely with d'Orbigny's figure, occurring at 

 several stations, but not in any considerable numbers. D 'Orbigny's 

 specimens were from Cuba; I have recorded the species also from 

 several stations from the north coast of Jamaica, and it seems to be 

 widely distributed in warm, shallow waters in the Indo-Pacific. It 

 is very questionable as to whether the specimens recorded by Brady 

 from a great depth in the Pacific really are identical with this species. 



Genus BILOCULINA d'Orbigny, 1826. 



Biloculina subspliaerica d'Orbigny. 



BUoculina suhsphcerica d 'Orbigny, in De la Sagra, Hist. Fis. Pol. Nat. Cuba, 1839, *' Forami- 

 niferes," p. 162, pi. 8, figs. 25 to 27. — Cushman, Proc. U. S. Nat. Mus., vol. 59, 

 1921, p. 73. 



The most common Biloculina in the Tortugas collection is this 

 small one described by d'Orbigny from Cuba and Jamaica. They 

 agree very well with d'Orbigny's original figure and description, and 

 also with specimens that I have had from the north coast of Jamaica. 



It is evidently common in the shallow water in the West Indian 

 region. The specimens are all small, the largest measuring but 

 slightly more than 0.5 mm. 



Biloculina millettii Cushman ? 



Miliolina durrandii Millett (in part), Journ. Roy. Micr. Soc, 1898, p. 268, pi. 6, figs. 8 to 10 



(not fig. 7). 

 Biloculina millettii Cushman, Bull. 71, U. S. Nat. Mus., pt. 6, 1917, p. 81, pi. 34, figs. 4, o. 



Test in front view broadly elHptical, in end view, compressed; chambers 

 biconvex; the periphery with a definitely developed carina; wall smooth, 

 except for occasional transverse ribs usually indistinct; aperture shghtly 

 produced, broadly elhptical, with a shghtly thickened border joining the 

 carina at its outer edge; the aperture with a small bifid tooth. 



Length of the Tortugas specimen 0.70 mm. 



There is a single specimen in the collection which has the com- 

 pressed form and the thin peripheral carina and large aperture which 

 characterizes this species. The specimen is, however, somewhat ir- 

 regular, and, being the only one found, it should await further 

 material before positive identification is made. 



