DESCRIPTIVE rATALOGFE OF RECENT FORAMINIFERA. 337 



Family X. NUMMULTNID^. 



Test calcareous and tiuely tubulated; typically free, polytbalauious 

 and syminotrically spiral. The higher moditlcatious all possessing" a 

 supplemental skeleton and a caual system of greater or less complexity. 



Svabfamily POIiYSTOISrELLINJE. 



Test bilaterally symmetrical; nautiloid, lower forms without supple- 

 mental skeleton or iuterseptal canals; higher types with canals ojjeii- 

 ing at regular intervals along the external septal depressions. 



Genus NONIONINA. 



Supiilemental skeleton absent or rudimentary; no external sei)tal 

 pores or bridges; aperture a simple curved slit. 



NONIONINA BOUEANA d'Orbigny. 

 (Plate 79, tig. 5.) 



Oval, compressed, bilaterally symmetrical; composed, of numerous 

 long, narrow, curved segments coiled in a close flat spiral, the last con- 

 volution completely inclosing the others; outline smooth; sutures flush; 

 surl'ace granular about the umbilici, which are depressed; no intersep- 

 tal pores. Diameter, about O.G mm. (/^ inch). 



Locality. — Gulf of Tokyo, 9 fathoms. 



NONIONINA SCAPHA Fichtel and Moil. 

 (Plate 80, fig. 1.) 



Oval, compressed, symmetrical, smooth, not granular about the 

 umbilici; segments comparatively few, increasing rapidly in size; face 

 of the terminal segment broad and round. Diameter, about 0,4 nun. 

 (,^0 iuch). 



Localities. — Panama Bay, coast of Yucatan, and (lulf of Tokyo 

 (stations 2805, 2358), 9 to 222 fathoms. 



Genus POLYSTOMELLA. 



Sup])lemental skeleton, septal bridges, and canal system more or 

 less fully developed : canals opening externally at the nndiilicus and 

 by a single or double row of pores along the sutures. Ai)erture a 

 V-shaped line of perforations at the base of the septal face. 



POLYSTOMELLA STRIATOPUNCTATA Fichtel and Moll. 

 (Plate 80, fig. 2.) 



Discoidal, bilaterally symmetrical; final convolution incloses all the 

 others; margin rounded; walls fiuelj' perforated; septal bridges dis- 

 tinct; a single row of pores along the sutures. Diameter, about O.G mm. 

 (/o luch). 



NAT MUS 97 22 



