34 BULLETIN 104, UNITED STATES NATIONAL MUSEUM 



ately after the proloculum, lateral chambers and pillars developed 

 at each side of the test. 

 Miocene of the East Indies. 



Genus HETEROCLYPEUS Schubert, 1906 



Heteroclypeus Schubert, Centralbl. fiir Min., 1906, p. 640. — Cushman, 

 Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, p. 214. 



Genoholotype. — -Heterostegina cycloclypeus A. Silvestri. 

 Test similar to Heterostegina in the young, but the chambers becom- 

 ing annular in the later development. 

 Tertiary. 



Genus CYCLOCLYPEUS W. B. Carpenter, 1856 



Cydoclypeiis W. B. Carpenter, Phil. Trans., 1856, p. 555. — Cushman, 

 Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, p. 214. 



Genotype, by designation. — Cycloclypeus carpenteri H. B. Brady. 



Test in the microspheric form like Heterostegina in the early stages, 

 later with the chambers becoming annular, divided by radial portions 

 into rectangular chamberlets, the test discoidal and much com- 

 pressed. 



Miocene to Recent. 



Family 26. PENEROPLIDAE 



Test imperforate except the proloculum and second chamber 

 which are distinctly perforate, calcareous, in general planispiral in 

 the young, then becoming annular or uncoiling; chambers typically 

 divided into chamberlets in all but the most primitive genera ; aperture 

 in the simpler forms slit-like, becoming multiple in the complex 

 forms or rounded and terminal in the uncoiled forms. 



Subfamily 1. Spirolininae 



Test close coiled in the young, often becoming uncoiled in the 



adult. 



Genus PENEROPLIS Montfort, 1808 



Peneroplis Montfort, Conch. Syst., vol. 1, 1808, p. 259. — Cushman, 

 Special Publ. No. 1, Cushman Lab. Foram. Res., 1928, p. 217. 



Coscinospira Ehrenberg, Abhandl. k. Akad. Wiss. Berlin, 1838, p. 131 

 (genotype, by designation, Coscinospira hemprichii Ehrenberg). 



W: Genoholotype. — Peneroplis lanatus Montfort = Nautilus planatus 

 Fichtel and Moll. 



Test free, planispiral, close coiled in the young, usually involute, 

 in the adult becoming variously shaped, close coiled, flaring, annular 

 or commencing to uncoil; chambers undivided; wall calcareous, 

 imperforate except in the proloculum and sometimes the following 



