578 EONALD ROSS AND R. FIELDING-OULD. 



one, the melaniu consists of coarse dark brown granules, tlie amoeboid move- 

 ments are slow, the spores are about eight to twelve in number, development 

 takes seventy-two hours. 

 Fig. 15.— Spore. 



Figs. 16—18. — Growth of amcebula. 

 Fig. 19. — First appearance of spore formation. 

 Fig. 20.— Sporocyte. 

 Fig. 21. — Freed spores. 

 Fig. 22. — Gametocyte. 

 Figs. 23 — 29.— Development of Hsemamoeba vivax, the parasite of 

 tertian fever of man. The containing corpuscle is nearly always an excep- 

 tionally large one, the melanin consists of very fine light brown granules, 

 amoeboid movements are rapid, the spores are about twelve to twenty in 

 number, development takes thirty-six hours. 

 Fig. 23.— Spore. 



Figs. 24 — 26. — Growtli of amoebula. 

 Fig. 27. — Sporocyte. 

 Fig. 28. — Freed spores. 

 Fig. 29.— Gametocyte. 

 Figs. 30 — 41. — Development of Ha;momenas prsecox, the parasite of 

 remittent, pernicious, or sestivo-autumnal fever of man. Several varieties, 

 which are possibly distinct species. The amcebuloe are small, contain only a 

 few clumps of black melanin, and retire to the spleen, bone-marrow, etc., on 

 approaching maturity ; the gametocytes have a special crescentic shape. 

 Figs. 30 — 34. — Growth of amcebula becoming a sporocyte. 

 Fig. 35. — Freed spores. 



Figs. 36 — 39. — Growth of amoebula becoming a gametocyte. 

 Fig. 40. — Male gametocyte (portion of red corpuscle still present). 

 Fig. 41, — Female gametocyte (remains of corpuscle entirely disa])peared). 

 Figs. 42 — 52. — Development of gametocytes of Hsemomenas prtecox 

 in stomach cavity of Anoplieles. 

 Fig. 42. — Male gametocyte. 

 Fig. 43. — Female gametocyte. 

 Figs. 44, 45. — Gametocytes become oval five minutes after ingestion by 



the gnat. 

 Figs. 46, 47. — Gametocytes become spherical a few minutes later. Polar 



bodies appear at the margin. 

 Fig. 48. — Male gametocyte emitting microgametes (the so-called "flagel- 

 late body"). 

 Fig. 49. — Female gametocyte or macrogamete awaiting fertilisation. 

 Fig. 50. — Free microgametes. 

 Fig. 51. — Microgamete entering macrogamete. 

 Fig, 52. — Fertilised macrogamete, or zygote. 



