26 



BULLETIN 104, UNITED STATES NATIONAL MUSEUM 



slightly inflated, very distinct; sutures slightly depressed, marked by 

 the very short, broad retral processes, averaging about 15 in number; 

 wall thin, translucent, smooth, conspicuously but finely perforate; 

 aperture composed of a series of small, rounded openings at the base 

 of the apertural face. 



Diameter, 0.50 mm.; thickness, 0.20 mm. 



D'Orbigny described and figured this species from shore sands of 

 Cuba and Jamaica. It has proved to be the most common species of 

 the genus in the general West Indian region. It is one of those species 

 which has been included under " Polystomella striato-pundaia" but is 

 very different from that species. 



There is a considerable amount of variation in the specimens of this 

 species, in the shape, which is often somewhat longer than broad and 

 especially in the number of the chambers. In its general characters, 

 however, it is distinct from any other in the region. 



Elphidium poeyanum — Material examined 



ELPHIDIUM ARTICULATUM (d'Orbigny) 



Plate 10, figures 6-8 



Polystomella articulata d'Orbigny, Voy. Amer. M^rid., vol. 5, pt. 5, 1839, 

 "Foraminiferes," p. 30, pi. 3, figs. 9, 10. 



Test small, somewhat compressed, periphery rounded, margin 

 slightly lobulate, sides nearly parallel in peripheral view, umbilical 

 regions slightly depressed; chambers averaging 10 in number in the 

 last-formed coil, slightly inflated; sutures slightly depressed, marked 



