12 BULLETIN 10 4, UNITED STATES NATIONAL MUSEUM 



Genus RAMULINA Rupert Jones, 1875 



Bull. 104, pt. 4, p. 177. 



Family 24. NONIONIDAE. — Family 25. CAMERINIDAE. — 

 Family 26. PENEROPLIDAE.— Family 27. ALVEOLINELLI- 

 DAE. (To be included in Part 7 of this Bulletin.) 



Family 28. KERAMOSPHAERIDAE 



(Not known from the Atlantic.) 



Family 29. HETEROHELICIDAE 



Test in the more primitive forms planispiral in the young, later 

 becoming biserial, in the more specialized genera the spiral and 

 biserial stages reduced or wanting and the relationships shown only 

 by other characters; wall calcareous, perforate, ornamentation in 

 specialized genera bilaterally symmetrical; aperture when simple, 

 usually large for the size of the test, without teeth, in some forms 

 with an apertural neck and phialine lip. 



Subfamily 1. Heterohelicinae 



Test in the early stages distinctly planispiral, later chambers 

 biserial; aperture large, at the inner margin of the chamber. 

 (Fossil — Cretaceous only.) 



Subfamily 2. Pavonininae 



Test with the planispiral stage much reduced, the biserial stage of 

 short duration and the adult with single chambers extending clear 

 across the face of the test or even becoming completely annular. 



Genus PAVONINA d'Orbigny, 1826 



Bull. 104, pt. 2, p. 51. 



Subfamily 3. Gumbelininae 



Test in the early stages of the microspheric form planispiral, often 

 skipped in the megalospheric form, followed by a biserial stage which 

 may be continued or may be followed by globular chambers 

 variously arranged. 



(Fossil — Cretaceous and Eocene.) 



Subfamily 4. BOLIVINITINAE 



Test in the adult biserial, compressed; aperture in the median line, 

 at the base of the inner margin. 



Genus BOLIVINITA Cushman, 1927 



Bull. 104, pt. 3, p. 44 (Bolivina rhomboidalis and B. quadrilatera) . 



