1906.] Observations on the Life-History of Leucocytes. 



59 



Plate 9. 



Figs. 9 and 10. — Prophases of division in cells of bone-marrow of guinea-pig, showing 



splitting of the so-called spireme thread. 

 Fra. 11. — Similar stage in the first maiotic prophase of division in the testis of guinea-pig. 

 Figs. 12 and 13. — First maiotic (heterotype) division figures from the bone-marrow of 



guinea-pig. 



Fig. 14. — Ditto from bone-marrow of rat. | 

 Fig. 15. — Division figure from bone-marrow of guinea-pig. 

 Fig. 16. — First maiotic division figure from testis of guinea-pig. 



Fig. 17. — Diaster stage from cell in bone-marrow of guinea-pig. Some of the chromo- 

 somes are longitudinally split. 



Figs. 18, 19 and 20. — Second maiotic (homotype) division figures from bone-marrow of 

 guinea-pig. 



Plate 10. 



Fig. 21. — Ditto from germinal area of lymphatic gland of guinea-pig. 

 Fig. 22. — View of equatorial plane of a division figure similar to those shown in figs. 18 

 to 21. 



Fig. 23. — Diaster stage of a similar figure. Bone-mairow, guinea-pig. (Compare with 

 fig. 8.) 



Figs. 24, 25 and 26. — Second maiotic division figures from testis of guinea-pig. 



Fig. 27. — Testis of embryo guinea-pig. A large male ovum and a homotype division 



figure among the cells which will form the foot-cells. 

 Fig. 28. — Ditto, showing somatic division figures. 



