38 SMITHSOXIAX MISCELLANEOUS COLLECTIONS VOL. ']'^ 



various forms between ; surface smooth or ornamented ; aperture 

 either radiate or with a definite neck and phiaHne lip. 



Genus LINGULINA d'Orbigny, 1826 

 Plate 7, fig- 4 

 Test compressed ; chambers arranged in a Hnear series, usually 

 closely set ; aperture usually elongate, corresponding to the form of 

 the chamber. 



Genus TRIFARINA Cushman, 1923 

 RHABDOGONIUM H, B. Brady, not Reuss 



Plate 7, fig. 5 



Test elongate, triangular in transverse section ; the early chambers 

 in an irregular spiral, later ones very loosely so or even uniserial ; 

 wall thin, translucent, finely punctate ; aperture terminal not radiate, 

 at the end of a short, often phialine lip. 



Genus CRISTELLARIA Lamarck, 1812 

 Plate 8, fig. I 



Test planospiral, typically close-coiled, but becoming much uncoiled 

 in some species ; chambers numerous ; wall hyaline, perforate, variously 

 ornamented : aperture usually distinctly radiate. 



Genus MARGINULINA d'Orbigny, 1826 

 Plate 7, fig. 6 



Test subcylindrical, early portion close-coiled, later chambers 

 uncoiled, rounded in transverse section, the last-formed chambers 

 often inflated ; aperture in early chambers marginal, later often becom- 

 ing nearly median, usually radiate. 



Genus VAGINULINA d'Orbigny, 1826 

 Plate 8, fig. 2 



Test elongate ; chambers in a linear series, placed so that the sutures 

 are oblique ; aperture marginal ; chambers laterally compressed. 



Genus FRONDICULARIA, Defrance, 1824 

 Plate 6, fig. 8 



Test compressed, in the adult consisting of chambers, elongate and 

 narrow, running back on either side of the test ; wall vitreous, finely 



