Vol. xxiii] ENTOMOLOGICAL NEWS 223 
gametoblast the nucleus divides into a number of parts (the 
number depending on the species of parasite) which arrange 
themselves near the wall, and from each of which is developed 
a flagellate microgamete. These are freed from the resting 
cell and being motile may find a macrogamete which one of 
them enters and fertilizes. Fhe fertilized macrogamete now 
becomes elongate and ovoid and is termed the odkinete, or 
wandering cell. It penetrates the wall of the stomach, and, 
passing through the epithelium, it encysts just under the base- 
ment membrane. These cysts occur mostly on the posterior 
cwo-thirds of the dilated part of the stomach. The resting 
cell or oocyst increases greatly in size as by nuclear division 
it produces many sporoblasts which in turn develop into 
sporozoites. When completely matured the cyst bursts liber- 
ating the sporozoites in the body cavity of the mosquito. 
They are carried around in the blood currents, and, pene- 
trating the salivary gland, surround the central canal down 
which they finally pass with the salivary secretion. The mos- 
quito in biting its victim, injects them into the blood and the 
life-cycle is complete. 
The nature of the diagram necessitates inaccuracies in 
structure such as for example the exaggerated length of the 
dilated portion of the stomach. On the other hand since not 
all mosquitoes are capable of transmitting the parasite, I have 
included such characteristics of Anopheles, the malarial bear- 
ing mosquito, as could be placed in such a diagrammatic rep- 
resentation. 
A Sration For INSTRUCTION AND RESEARCH IN Broxocy will be main- 
tained by the University of Michigan from July 2 to August 23 in- 
clusive, 1912, near the Bogardus Engineering Camp of the University 
‘on a tract of land stretching from Douglas Lake to Burt Lake in 
Cheboygan County, Michigan. Since the number of students that can 
be accommodated is limited, immediate registration is necessary to 
insure admission and no registration will be accepted if received after 
June 1st. Applications for admission should be addressed to Professor 
T. E. Rankin, Secretary of the Summer Session, Ann Arbor, Mich. 
Among the courses offered is one on the Natural History of Insects 
by Professor Frank Smith and Mr. Paul S. Welch, of the University 
of Illinois. 
