526 DR MASTERMAN ON THE FURTHER ANATOMY AND 



LIST OF REFERENCES. 



(1) HaemeRj S. F., Appendix to Challenger Report on " Cephalodiscus.' 1 



(2) ,, Zoologischen Anzeiger, No. 543, 1897. 



(3) Lankester, E. R., Quart. Journal Micros. Science, 1884. 



(4) M'Intosh, W. C, Challenger Report on " Cephalodiscus." 



(5) Masterjian, A. T., Quart. Journal Micros. Science, August 1897 



(6) „ Zoologischen Anzeiger, No. 545, 1897. 



(7) „ Proc. Royal Soc Edin., March 1896. 



LIST OF PLATES. 



Plate 1. 



Figs. 1-9. Series of coronal longitudinal sections through pharynx of Cephalodiscus (camera). 

 Figs. 10-15. Series of nearly transverse sections through gonads of Cephalodiscus. 

 Fig. 16. Semi-diagrammatic longitudinal section through the gonad and gonaduct of Cephalodisai*. 

 Fig. 17. Semi-diagrammatic longitudinal section through nephridium and gonad of Phoronis. 

 Fig. 18. Transverse section through (pedicle) ventral sucker of Cephalodiscus. 



Plate II. 



Fig. 19. View of pedicle of Cephalodiscus with two young buds. 

 Fig. 20 Dorsal view of older bud. 

 Fig. 21. Lateral view of next stage. 

 Fig. 22. Dorsal view of the same stage as fig. 21. 

 Fig. 23. Dorsal view of bud with one pair of plumes. 

 Fig. 24. Dorsal view of slightly later stage. 

 Fig. 25. Lateral view of bud with two pairs of plumes. 

 Fig. 26. Ventral „ „ 



Fig. 27. Ventral view of free bud with three pairs of plumes, with buccal shield, and post-orol 

 lamella removed. 



Fig. 28. Lateral view of slightly later stage of free bud. 



Plate III. 



Figs. 29-32. Series of transverse sections through right-hand bud figured in fig. 19. 



Figs. 33-35. ,, ,, left-hand bud „ 



Fig. 36. Longitudinal sagittal section through a bud similar to right-hand bud in fig. 19. 



Fig. 37. Sagittal section through bud shown in fig. 20. 



Fig. 38. Horizontal „ „ 21. 



Fig. 39. Sagittal „ „ 22. 



Figs. 40-48. Series of transverse sections through bud in fig. 23. 



Figs. 49-59. „ „ 24. 



