56 BULLETIN 161, UNITED STATES NATIONAL MUSEUM 



Test subcircular in front view, somewhat compressed, periphery 

 rounded; chambers distinct; sutures slightly depressed; wall orna- 

 mented by numerous longitudinal costae ; aperture semicircular, with 

 a slight tooth, which in side view projects beyond the outline of 

 the aperture, and sometimes shows a distinct perforation. Diameter, 

 0.55-0.8 mm. ; thickness, 0.4-0.45 mm. 



This is one of the typical West Indian species described by 

 d'Orbigny from Cuba and Jamaica. There are numerous records 

 for it in the general West Indian region, and our material shows 

 that it extends definitely into the Indo-Pacific, although much of 

 the material that has been referred to this species is not the same 

 as the species described by d'Orbigny. The only tj^pical material 

 we have is from Guam Anchorage, Ladrone Islands, 21 fathoms, 

 one of which is here figured. 



TRILOCULINA SPINATA, new species 

 Plate 12, Figuees 5 o-c 



Test elongate, fusiform, periphery rounded, the basal end extend- 

 ing into a definite pointed spine, the apertural end extended into a 

 long cylindrical neck; chambers distinct, somewhat inflated; sutures 

 distinct, not depressed; wall smooth; aperture circular with a very 

 slight lip and a very small simple tooth, which may or may not be 

 present. Length, 0.6 mm.; breadth, 0.12 mm.; thickness, 0.1 mm. 



Eolotype. — Cushman Coll. No. 14633, from Rongelap Atoll, Mar- 

 shall Islands. 



This very distinctive species occurs only at the type locality, but 

 a number of specimens were present to give the full characters of 

 the species, which were very constant. The spine at the basal end 

 is very well developed and is a rather unique feature in this group. 



TRILOCULINA TRIGONULA (Lamarck) 



Plate 13, Figures 1 a, o 



Miliola trigonula Lamabck, Ann. Mus. d'Hist. Nat., vol. 5, p. 351, No. 3, 1804 ; 

 vol. 9, pi. 17, fig. 4, 1807. 



Triloculina trigonula, d'Orbigny, Ann. Sci. Nat., vol. 7, p. 299, No. 1, pi. 16, 

 figs 5-9, 1826 ; Modeles No. 93, 1826.— Cushman, U. S. Nat. Mus. Bull. 104, 

 pt. 6, p. 56, pi. 12, figs. 10, 11 ; pi. 13, figs. 1, 2, 1929.— Cushman and Valen- 

 tine, Contr. Dept. Geol. Stanford Univ., vol. 1, no. 1, p. 16, pi. 4, figs. 7 a~-c, 

 1930. 



Miliolina trigonula Williamson, Rec. Forani. Great Britain, p. 84, pi. 7, figs. 

 180-182, 1858.— H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, p. 164, 

 pi. 3, figs. 14-16, 1884. 



Test in the adult with three visible chambers, the angles rounded, 

 the periphery broadly convex, whole test somewhat longer than 



