Contents 



Page 



Preface v 



Part 1: Planktonic Foraminifera 1 



1. Planktonic foraminiferal families Hantkeninidae, OrbulLnidae, Globorotaliidae, and 



Globotruncanidae (Text-figs. 1-9, pis. 1-11) 3 



By Hans M. Bolli, Alfred R. Loeblich, Jr., and Helen Tappan 



2. The genera Praeglohotruncana, Rotalipora, Globotruncana, and Abathomphalus in the 



Upper Cretaceous of Trinidad, B. W. I (Text-fig. 10, pis. 12-14) 51 



By Hans M. Bolli 



3. The genera Globigerina and Globorotalia in the Paleocene-lower Eocene Lizard 



Springs formation of Trinidad, B.W.I (Text-figs. 11-13, pis. 15-20) 61 



By Hans M. Bolli 



4. Chiloguembelina Loeblich and Tappan and related Foraminifera from the lower 



Tertiary of Trinidad, B.W.I (Text-figs. 14-16, pi. 21) 83 



By J. P. Beckmann 



5. Planktonic Foraminifera from the OUgocene - Miocene Cipero and Lengua forma- 



tions of Trinidad, B. W. I (Text-figs. 17-21, pis. 22-29) 97 



By Hans M. Bolli 



6. Some planktonic Foraminifera of the type Danian and their stratigraphic im- 



portance (Text-figs. 22-24, pi. 30) 125 



ByJ. C. Troelsen 



7. A revision of the foraminiferal family Heterohelicidae (Pis. 31-34) 133 



By Eugenia Montanaro Gallitelli 



8. Planktonic Foraminifera from the Eocene Navet and San Fernando formations of 



Trmidad, B. W. I (Text-figs. 25-26, pis. 35-39) 155 



By Hans M. Bolli 



9. Planktonic Foraminifera of Paleocene and early Eocene age from the Gulf and 



Atlantic Coastal Plams (Text-figs. 27-28, pis. 40-64) 173 



By Alfred R. Loeblich, Jr., and Helen Tappan 



Part 2: Benthonic Foraminifera 199 



10. NewCretaceousindexForaminiferafromnorthernAlaska . (Text-fig. 29, pis. 65-71) 201 



By Helen Tappan 



11. Eleven new genera of Foraminifera (Text-fig. 30, pis. 72-73) 223 



By Alfred R. Loeblich, Jr., and Helen Tappan 



12. The foraminiferal genus Crucilocvlina d'Orbighy, 1839 (PI. 74) 233 



By Alfred R. Loeblich, Jr., and Helen Tappan 



Plates 237 



Index 313 



m 



