DESCRIPTION OF THE PLATES. 
NOTE. — P/^tcs /., //., afid III. consist of photographs taken mostly from unstained preparations 
preserved in formalin. Formalin accentuates the outline of the zygotes ; on the other hand, a small amount of 
detail has been lost in the collotype process. Hence the result is that the photographs show the parasites almost 
exactly as they are seen in fresh preparations of the tissues of the gnat, except that the granules of melanin 
do not come out with sufficient clearness in all the figures. None of the photographs have been in any way 
retouched by hand. 
PLATE I. 
Figure I ( x 500). — Very small zygotes of Hamamoeba relicta attached to stomach wall of Culex fatigans. 
The melanin has become enlarged by the formalin. Coloured. 
Figu!-e 2 (x 500). — Very small zygotes of H. relicta attached to stomach wall of C. fatigans. Unstained. 
I'he melanin is of the natural size. 
Figure 3 (x 500). — Very small zygotes of H. vivax attached to stomach wall of Anopheles costalis. 
Unstained. Melanin scarcely appreciable in the collotype. 
Figure 4 (x 500). — Very small zygotes of H. malariae in A. funestus. Unstained. 
Figure 5 (x 500). — Small zygotes of Heemome?ias precox in A. costalis. Unstained. 
Figure 6 (x 500). — Small zygotes of//, malaria in A. costalis. Unstained. 
PLATE II. 
Figure ~ (x 500). — Larger zygotes of H. relicta in C fatigans. One well shown protruding into the 
bod}- cavity of the host. Unstained. 
Figure 8 (x 500). — Still larger zygotes of H. vivax in A. costalis, showing great delicacy of the outline. 
Unstained. 
Figure 9 (x 500). — Medium sized zygotes of one of the human species in A. costalis. The focal plane 
is taken through one of the blastophores (in the middle of the zygote). The blasts are already 
nearly mature. Unstained. 
Figure 10 (x 500). — A zygote of H. relicta about two-thirds of the full size, protruding into body cavity, 
and containing blasts which are already nearly mature. Unstained. 
Figure 1 1 ( x 500). — A full-sized zygote of H. relicta full of mature blasts, many of which are seen to be 
paciced side by side (near the lower margin). Unstained. 
Figure 12 (x about 60). — Stomach of C. fatigans with mature zygotes of//, relicta, as seen by a low power. 
Coloured. 
PLATE III. 
Figure 13 (x 500). — Mature zygote of H. relicta full of blasts ; and also capsule of another (to the left) 
containing " black spores." Unstained. 
Figure 14 (x about 400). — Blasts and "black spores" of H. relicta in C. fatigans, apparently ejected 
together from the capsule of a zygote. Unstained. The "black spores" do not seem to be 
mature. 
Figure 15 (>< 400). — Blasts of H. relicta lying free in the juices of the thorax of C. fatigans. Unstained. 
Many lie in perspective. 
Figure 16 (x 500). — Four blasts of//, relicta in juices of C. fatigans, dried and stained. 
Figure 17 (x 500). — Blasts of H. relicta, dried but not stained. 
Figure 18 (x about 400). — Blasts of one of the human Ha:mamcebidae in the salivary gland of A. costalis. 
Unstained. The blasts are closely packed within the salivary cells, and also lie outside the cells, 
within the capsule. 
PLATE IV. 
Drawings, by Dr. Fielding-Ould, of the Ha;mamoebida2 found by him in Anopheles in Sierra Leone. 
Figures 1-9. — Zygotes — apparently of //. vivax. 
Figure 10. — A zygote discharging blasts. 
Figure 11. — Individual blasts. 
PLATE V. 
Drawings of Anopheles costalis and Anopheles funestus. Made at the British Museum. 
