56 



egg moves. The vermiculus stage can be seen on 

 the shde in the case of halteridium, but in the case 

 of malaria parasites, only by taking the blood 

 from the stomach of the mosquito after a suitable 

 lapse of time. The vermiculus now finds its way 

 through the epithelium of the stomach, and then • 

 lies in the external muscular layers as a spherical i 

 or ovoid body, the zygote. A kind of capsule is : 

 formed around it by these tissues, and so at this : 

 stage it is also called the Oocyst. Growth proceeds, ' 

 and signs of division into several masses appear 

 in the protoplasm. These masses are termed 

 sporoblasts. Then we reach the stage of large 

 zygote (with sporoblasts), and by this time the 

 masses of the sporoblast have undergone division 

 into a number of fine curved thread-like bodies, 

 the sporozoits, so that eventually the large cyst is 

 almost entirely filled with sporozoits. The capsule 

 of the cyst eventually ruptures, and the sporozoits 

 pass from the tissues of the stomach to the thorax, 

 being found at first amidst the muscles, but 

 eventually all collected in the salivary glands. 

 From' here they are injected into the blood by the 

 mosquito, and they then attach themselves to and 

 penetrate the red cells (as has been actually 

 observed under the microscope by Schaudinn), 

 producing a new infection. 



We may briefly summarize tliese various 

 steps : — 



1. Mikrogametocyte, and makrogamete in 

 blood. 



2. Development of mikrogametes = flagella- 

 tion, on the slide and in nature in stomach of an 

 Anopheline. 



