44 



BULLETIN 104, UNITED STATES NATIONAL MUSEUM 



wall longitudinally striate ; aperture consisting of a series of independ- 

 ent pores in the central portion of the apertural face. 



This species, often abundant in the Mediterranean and Indo- 

 Pacific, is very rare in the western tropical Atlantic. Woodward 

 records it from Bermuda, and I collected it there also, but it was 

 very rare. It occurs at the Tortugas, but there also it is very rare. 

 I found it rare also at Montego Bay, Jamaica. 



This is evidently a widely distributed form occurring but in small 

 numbers in the general West Indian region. 



SpiroUna arielinus — Material examined 



Genus MONALYSIDIUM Chapman, 1900 



Monalysidium Chapman, Journ. Linn. Soc. Zool., vol. 28, 1900, p. 3 (as a 

 subgenius of Peneroplis) . — Cushman, Publ. 311, Carnegie Instit. Washing- 

 ton, 1922, p. 80; Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, 

 p. 218. 



Genotype, by designation. — Monalysidium sollasi Chapman. 



Test with the early chambers close coiled, later ones uncoiled in a 

 rectilinear series; wall imperforate, smooth or with vertical rows of 

 minute tubercles ; aperture circular, terminal, sometimes with a short 

 neck and lip. 



Recent. 



The early chambers of specimens are easily broken, and it is usual 

 to find only the uniserial chambers present after samples are washed. 

 The constrictions at the sutures leave the test very weak. The neck 

 and lip that are developed are similar to those seen in so many of the 

 uncoiled genera of various families of the foraminifera. 



monalysidium POUTUM Chapman (7) 



Plate 15, figures 11, 12 



Peneroplis lituus H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, 



p. 205, pi. 13, figs. 24, 25 (?). 

 Peneroplis {Monalysidium) polita Chapman, Journ. Linn. Soc. London, 



Zool., vol. 28, 1902, p. 4, pi. 1, fig. 5 (?). 

 Monalysidium polita Hebon-Allen and Earland, Trans. Zool. Soc. London, 



vol. 20, 1915, p. 603, te.xt fig. 43 G.— Cushman, Publ. 311, Carnegie Instit. 



Washington, 1922, p. 80, pi. 13, fig. 4; Publ. 344, 1926, p. 84. ^j^ 



