FORAMINIFERA OF THE ATLANTIC OCEAN 13 



Subfamily 5. Spiroplectinatinae 



Test elongate, early position clearly planispiral, later biserial or 

 uniserial; wall calcareous, perforate. 

 (Not included in the Atlantic.) 



Subfamily 6. Plectofrondicularinae 



Test in the microspheric form planispiral in the early stages, later 

 biserial and then uniserial or in the higher forms starting as uniserial 

 tests; ornamentation bilaterally symmetrical; aperture rounded or 

 elliptical, terminal. 



(No Atlantic species.) 



Subfamily 7. EouviGERiNiNAE 



Test in the earliest stages biserial, later triserial or in the most spe- 

 cialized genera uniserial after the triserial stage or throughout. 

 (No Atlantic forms described.) 



Family 30. HANTKENINIDAE 



Test planispiral, at least in the young, involute; each chamber 

 with a long acicular spine; wall calcareous, perforate or in some 

 species vesicular on the exterior; aperture, a high arched opening often 

 with basal lobes or divided. 



(No Atlantic forms.) 



Family 31. BULIMINIDAE 



Test typically an elongate spiral, divided into chambers, in the 

 specialized genera biserial or uniserial or even monothalamous; wall 

 calcareous, perforate; aperture loop-hke or rounded and terminal, 

 usually with some sort of apertural tooth or spiral connected with the 

 interior tubular siphons connecting the apertures. 



Subfamily 1. Terebralininae 



Test in an elongate, close spiral; not divided into chambers; aper- 

 ture rounded, subterminal. 

 (Fossil — Jurassic . ) 



Subfamily 2. TURRILININAE . 



Test, an elongate close spiral, divided into chambers, usually more 

 than three to a whorl, the lines of the spiral very distinct. 



Genus BULIMINELLA Cushman, 1911 



Bull. 104, pt. 3, pp. 108-113. 



Genus BULIMINOIDES, Cushman, 1911 



Bull. 104, pt. 3, p. 113. 



