FORAMINIFERA 403 



Genus Pavonina d'Orbigny (Fig. 188, d) 



Test planispiral, bi- or tri-serial with elongate spines and lobed 

 aperture; fossil and recent Family 29 Hantkeninidae 



Genus Hantkenina Cushman (Fig. 188, e) 



Test typically with an internal tube, elongate 



Aperture generally loop-shaped or cribrate; fossil and recent. . . 

 Family 30 Buliminidae 



Genus Bolivina d'Orbigny (Fig. 188, /) 



Aperture narrow, curved, with an overhanging portion; mostly 

 fossil, also recent Family 31 Ellipsoidinidae 



Genus Ellipsoidina Seguenza 



Test trochoid, at least in young of microspheric form, usually coarsely 

 perforate; when lenticular, with equatorial and lateral chambers 

 Test trochoid throughout, simple; aperture ventral 



No alternating supplementary chambers on ventral side; fossil 

 and recent Family 32 Rotaliidae 



Genus Rotalia Lamarck (Fig. 188, g) 



Genus Spirillina Ehrenberg (Fig. 184, A) 



Genus Patellina Williamson. 



Genus Discorbis Lamarck (Fig. 184, B) 



Alternating supplementary chambers on ventral side; fossil and 

 recent Family 33 Amphisteginidae 



Genus Asterigerina d'Orbigny (Fig. 188, h) 



Test trochoid and aperture ventral in young 



With supplementary material and large spines, independent of 

 chambers; fossil and recent Family 34 Calcarinidae 



Genus Calcarina d'Orbigny (Fig. 189, a) 



With later chambers in annular series or globose with multiple 

 apertures, but not covering earlier ones; fossil and recent. . . . 

 Family 35 Halkyardiidae 



Genus Halkyardia Heron-Allen and Earland (Fig. 189, h) 



With later chambers somewhat biserial; aperture elongate in 

 the axis of coil; fossil and recent. .Family 36 Cassidulinidae 



