CONTENTS xvii 



PAGE 



5. DEVELOPMENT OF BILOBITES 399 



Developmental Changes in BUobites various .... 402 



Observations 404 



6. DEVELOPMENT OF TEREBRATALIA OBSOLETA DALL . . 



7. DEVELOPMENT OF THE BRACHIAL SUPPORTS IN DIE- 



LASMA AND ZYGOSPIRA 410 



Development of the Loop in Dielasma turgidum . . . 412 

 Development of the Brachial Supports in Zygospira 



recurvirostris 413 



Observations and Correlations 415 



IV. MISCELLANEOUS STUDIES IN DEVELOPMENT 



1. DEVELOPMENT OF A PALEOZOIC PORIFEROUS CORAL . . 421 



Development of Pleurodictyum lenticular e 422 



General Conclusions 425 



2. SYMMETRICAL CELL DEVELOPMENT IN THE FAVOSITID^E 429 



Summary 433 



3. DEVELOPMENT OF THE SHELL IN THE GENUS TOR- 



NOCERAS HYATT 435 



V. PLATES AND EXPLANATIONS. 441 



INDEX 597 



