LIFE-HISTORY OF THE PARASITES OF MALARIA 187 
We divide the haemamoeba into two genera (Nature, August 3, 1899), 
namely : — 
Genus I — Haemamoeba, Grassi and Feletti. The gametocytes have a 
shape like that of the sporocytes before the spores have been produced. 
Genus II — Haemomenas, gen. nov. (syn. Laverania, Grassi and Feletti, in 
part). The gametocytes have a special (crescentic) shape. 
DESCRIPTION OF PLATES 
Illustrating Major Ronald Ross's and Dr. R. Fielding-Ould's paper on 
The Life-History of the Parasites of Malaria. 
Figs. 1-41 Illustrate the two avian species and the three human species in the blood-vessels 
of the vertebrate hosts. 
Figs. 42-52 Illustrate the development of the gametocytes of one of the human species, selected 
for the purpose, in the stomach cavity of anopheles, or in a drop of blood freshly extracted from the 
finger (in which the parasites develop much as they do in the stomach cavity of the insects). 
Figs. 53-67 Illustrate the further development of the parasites in the tissues of the gnat. 
Figs. 1-7 Development of Haemamoeba Danilewskii (syn. Halteridium Danilewskii, Labbe) in 
the blood of pigeons, jays, crows, etc. The amoebula is elongated, and lies by the side of the nucleus 
without disturbing its position. Several varieties exist. 
Fig. 1 Spore. 
Figs. 2-4 Growth of amoebula. 
Fig. 5 Sporocyte. 
Fig. 6 The containing corpuscle has burst, leaving nucleus, melanin, and free spores. 
Fig. 7 Gametocyte. 
Figs. 8-14 Development of haemamoeba relicta (syn. Proteosoma Grassii, Labbe) in the blood 
of sparrows, larks, crows, etc. The amoebula lies at one end of the corpuscle, and pushes the nucleus 
towards the other end. 
Fig. 8 Spore. 
Figs. 9-1 1 Growth of amoebula. 
Fig. 1 2 Sporocyte. 
Fig. 1 3 Freed spores. 
Fig. 14 Gametocyte. 
Figs. 15-22 Development of haemamoeba malariae, the parasite of quartan fever of man. The 
containing corpuscle is a small or medium-sized one, the melanin consists of coarse dark-brown granules, 
the amoeboid movements are slow, the spores are about eight to twelve in number, development takes 
seventy-two hours. 
Fig. 1 5 Spore. 
Figs. 16-18 Growth of amoebula. 
Fig. 19 First appearance of spore formation. 
Fig. 20 Sporocyte. 
Fig. 2 1 Freed spores. 
Fig. 22 Gametocyte. 
Figs. 23-29 Development of haemamoeba vivax, the parasite of tertian fever ot man. The 
containing corpuscle is nearly always an exceptionally 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. 
