DESCRIPTIVE CATALOGUE OF RECENT FORAMINIKERA. 263 



Test irregularly branching Subfamily Ramimmxi:. 



Composed of spherical or pyriform chambers, connected by Long stoloniferons 

 tubes Genus Hum it Una. 



Family VII. ChiLOSTOMELLID^E. 



Segments oval, each springing from the base of the previous one and entirely envel- 

 oping it (Jen us Ellipsoidina. 



Segments oval, put on alternately at either end of the test Genus Chilostomella. 



Segments alternating at three sides so as to leave exposed portions of two segments 

 and the whole of the final one (Jen us Allomorphina. 



Family VIII. Globigerinid.k. 



Test a single spherical chamber perforated with large and small foramina: 



Genus Orbulina. 

 Test rotaliform, trochoid or planospiral; segments few, inflated, coarsely perforated : 



Genus Globigerina. 

 Test regularly nautiloid and involute; walls thin, finely perforated, spinous: 



Genus Hastigerina. 

 Test regularly or obliquely nautiloid and involute; walls thick, smooth, very finely 



perforated Genus Pullenia. 



Test nearly globular, composed of a few coiled segments Genus Sphceroidina. 



Test trochoid, segments inflated, finely perforated ; aperture consisting of rows of 

 pores along the septal depressions Genus Candeina. 



Family IX. Rotaeid.k. 



Test spiral, nonseptate Subfamily Spirillininje. 



A complanate, nonseptate tube, free or attached Genus Spirillina. 



Test spiral, septate, rotaliform; rarely evolute, very rarely irregular or acervuline: 



Subfamily Rotalin.k. 



Conical; consisting of an external spiral or annular layer of chambers, the 

 interior of the cone being filled with hyaline substance or by a mass of com- 

 pressed chambers Genus Patellina. 



Trochoid or complanate, spiral at the apex, later segments often annular or 

 irregular; apertures opening into a deep central vestibule, or sometimes con- 

 sisting of sutural pores or bordered foramina Genus Cymbalopora. 



Trochoid or planoconvex, rarely complanate; rather coarsely porous; aperture 

 an arched slit at the umbilical margin of the last segment, often protected by 

 an umbilical flap Genus Discorbina. 



Complanate; early .segments spiral, later ones cyclical; apertures peripheral : 



Genus Planorbulina. 



Upper side usually more convex than the lower; very finely porous; aperture a 

 large slit at the umbilical end of the inferior sutural margin of the last seg- 

 ment Genus Pulvinulina. 



Lower side usually the more convex; very finely porous; aperture a neatly 

 arched slit near the middle of the inferior sutural margin of the last segment: 



Genus liotalia. 



Lower side usually the more convex; coarsely porous ; aperture near the outer 

 end of the final suture, sometimes with a phialine neck. ..Genus Truncatulina. 



Nearly alike on the two faces; coarsely porous Genus Anomalina. 



Lenticular, periphery furnished with radiating spines Genus Calcarina. 



Convex or monticulate, adherent; segments few, spreading radially or super- 

 imposed; aperture at the end of the final segment Genus Carpenteria. 



Columnar, adherent by a slightly spreading base; segments numerous, spiral; 

 aperture at the inner margin of the liual segment ...Genus Bupertia. 



