Plate VI. 



Fig. i. Echinosigra (Pourtalesia) phiale, abactinal side. 7/ z . (For the apical system and adjoining 



plates, comp. PI. VII. Fig. 7.) 



— 2. — — — side view. 7/ I# 



— 3. — — paradoxa, actinal side. r - 8 /i- 



— 4. — — — side view. I-8 /i- 



— 5. — — — abactinal side. I - 8 / I . 



— 6. — — — side view. I - 8 / I . 



— 7. — — phiale, actinal side. i\ z . 



— 8. Plexcchinus hirsutus, end view. */ t . 



— g. — — actinal side. 2 / z . 



— 10. Urechinus naresianus, actinal side. I, s/i- 



— 11. - J - 5 /i- 



— 12. Plexechinus hirsutus, abactinal side. */ z . 



- 13. - - Vi- 



— 14. — — side view. 2 / z . 



- 15. - - - »/* 



— 16. — actinal side. i; s/ z . (Not the same specimen as Figs. 12 and 15). 



— 17. Echinosigra (Pourtalesia) paradoxa, abactinal side. 6 / I . (For the apical system and adjoining 



plates, comp. Text-fig. 14, p. 75.) 



— 18. — — abactinal side. 1,8 / I . 



— 19. — — side view. 6 f z . 



— 20. — — actinal side. I-8 / I . 



— 21. - - - - - 7- 



