NO. 4 FORAMINIFERA CUSHMAN 33 



the young at the base of the inner margin of the last-formed chamber, 

 as in Tcxtularia, but in the adult, in the uniserial portion terminal, 

 rounded or oval according to the form of the chamber. 



Genus CLIMACAMMINA H. B. Brady, 1876 



Test arenaceous with a calcareous base, early chambers biserial, 

 later ones uniserial; aperture of numerous rounded pores. 



Genus BOLIVINA d'Orbigny, 1839 

 Plate 4, fig. 10 



Test elongate, distinctly biserial throughout ; wall usually thin and 

 hyaline in the young, but becoming thickened with age in many 

 species, ornamented by punctse, stride, costse, knobs, and spines, 

 with carinse developed in some species ; aperture elongate, usually 

 symmetrical. 



Genus PLEUROSTOMELLA Reuss, i860 

 Plate 5, fig. 2 



Test elongate, somewhat compressed, composed of numerous 

 chambers, usually biserially arranged ; wall calcareous, perforate, 

 smooth or ornamented ; aperture distinctive, an arched opening with 

 a vertical notch or slit in the middle of the lower edge usually with 

 tooth-like projections upward at either side. 



Genus PAVONINA d'Orbigny, 1826 



Plate 5, fig. 3 



Test calcareous, hyaline, perforate, many chambered, the early 

 chambers biserial, the later ones becoming uniserial, broad, curved-, in 

 the type species finally becoming embracing, and the embracing series 

 each composed of one or more chambers ; apertures numerous on 

 the peripheral margin. 



Genus CUNEOLINA d'Orbigny, 1839 



Test biserial, tapering, broadest near the apertural end, compressed 

 so that the two alternating series of chambers form a zigzag line on 

 the narrow sides of the test ; chambers numerous, low, and very broad, 

 wall arenaceous, composed of very fine material, smooth, chamber 

 wall labyrinthic, composed of numerous openings, the smaller near 

 the exterior ; aperture elongate, narrow, either simple or a row of 

 pores. 



