zoites can be readily recognized in many (Fig. 12, 8), though not in all, of the cells, especially in those of the middle lobe, and also free in the contents of the ducts. So numerous are they in some of the cells that the appearance they present is suggestive of a bacillus-laden lepra cell.
Fig. 14.—Dissection of head of mosquito.
A Median section of head, showing du, the veneno-salivary duct, with its insertion in hy, the hypopharynx; cb, cerebrum; below this are the cerebellum and the pumping enlargement of œ, the œsophagus; m. muscle; n, nerve commissure. The other parts have been removed. B, the veneno-salivary duct, showing its bifurcation and the three glands on one of its branches; pg, poison gland; sg marks the upper of the two salivary glands C, The bifurcation of the duct with its nucleated hypodermis.
Transference to the Human Host
By a large number of experiments, abundantly confirmed, Ross distinctly proved that if appropriate birds are bitten by mosquitoes whose salivary glands contain the sporozoites of the avian plasmodium, the birds become infected with the parasite, and in
