BY T. HARVEY JOHNSTON AND J. BURTON CLELAND. 513 



Fig. 3. — Host-nucleus quite divided by parasite. 



Fig- 10. — Encapsuled form free in plasma (blood from heart). 



Fig. 11. — Encapsuled form free in plasma (blood from liver;. 



Figs. 12,13. — Erythrocytes of Monacanthus sp., showing "ring" bodies. 



Fig. 14, — Erythrocytes of Chelodina longicollis with centrosome. 



Figs. 15-17. — Halteridium nettionis in erythrocytes of Nettion caHtaneum. 



Fig. 15. — Male form. 



Fig. 16. — Female form. 



Fig. 1 7. — Young intermediate form. 



Fig. 18. — Erythrocyte of Chelodina ohlonga showing centrosome. 



Figs. 19-24. — Plasmodium passeris in erythrocytes of Passer domesticus. 



Fig. 19. — Young amoeboid non-pigmented parasite. 



Fig. 20. — Double infection by young forms. 



Figs, 2 1,22. — 'Adult form, host-nucleus displaced. 



Fig. 23. — Adult form, host-nucleus expelled. 



Fig. 24. — Young pigmented form. 



Fig. 25. — Spirochaeta ratti from caecum of Miis rattus. 



Keferences to lettering: — ?i., host-nucleus—^., parasite — c, capsule of 

 parasite. 



All figures have been drawn, using the same magnification. 



54 



