PLATE XII 



DEVELOPMENT AND CLASSIFICATION OF 

 BRACHIOPODA. 



GLOTTIDIA ALBIDA HINDS (PAGE 269) 



FIGURE 1. Nepionic shell; Obolella stage. X 36. 

 FIGURE 2. Neanic stage ; showing anterior growth producing Lin- 

 gula-like form. X 16. 



FIGURE 3. Ephebic stage. X f- 



ORBICULOIDEA MINUTA HALL (PAGE 269) 



FIGURE 4. Nepionic shell; Palermo, stage. X 36. 



FIGURE 5. Neanic stage ; first holoperipheral growth, x 16. 



FIGURE 6. Ephebic stage. X 10. 



LEPT^NA RHOMBOIDALIS WILCKENS (PAGES 268, 269) 



FIGURE 7. Nepionic stage, with short hinge. X 36. 

 FIGURE 8. Early neanic stage, with radiating strise. X 10. 

 FIGURE 9. Ephebic stage. X f 



TEREBRATULINA SEPTENTRIONALIS COUTHOUY 

 (PAGES 268, 269) 



FIGURE 10. Nepionic stage, with open delthyrium. X 26. 

 FIGURE 11. Early neanic stage, with radiating strise. X 16. (After 

 Morse.) 



FIGURE 12. Ephebic stage, x f . (After Davidson.) 



