222 ENTOMOLOGICAL NEWS. [ May, ’12 
to represent graphically the main features of this life-cycle, as 
simply and accurately as possible. 
It has seemed worth while to include more of the details 
and to represent the whole less diagrammatically than in the 
work cited. The nomenclature adopted is that of Schaudinn. 
By means of the double-headed mosquito I have endeavored 
to show how the infection takes place through the biting of 
the human victim and how multiplication takes place asexually 
in the blood of that victim and sexually in the body of the 
mosquito which has bitten the malarial patient. 
At “A” the spindle-shaped sporozoite is injected into the 
finger together with the salivary secretion of the mosquito. It 
develops into the pale amceboid schizont which enters the blood 
corpuscle, and developing there at the expense of the heemo- 
globin, it deposits the characteristic melanin granules which 
are excretory in nature. 
These developing parasites are of two kinds. Many of them 
having become crescent-shaped within the corpuscles may be 
sucked up by the mosquito biting the malarial patient as at 
“B.” Others however are destined to increase their kind by 
sporulation in the blood of man. In these individuals the nu- 
cleus breaks up, the elements arranging themselves near the 
wall. Partitions begin to grow in from the wall until the 
nuclei are entirely separate from one another and finally the 
individual spores or merozoites are set free in the blood plas- 
ma by the disintegration of the corpuscle. Many of these are 
of course attacked and destroyed by the white corpuscles, but 
many enter healthy red corpuscles and repeat the entire 
process or develop into the type which, if swallowed by the 
mosquito) begin a new development in the stomach of the in- 
Sectvat aG.7 
The crescents are the gametes. They leave the corpuscles, 
become spherical in form anddevelop into either micro- 
gametoblasts (male) or macrogametes (female). In the latter 
case a small round body (perhaps a “polar” body) is extruded 
and finally thrown off so that at this stage the mature macro- 
gamete is ready for fertilization. In the case of the micro- 
