344 
Oriental Sore 
PLATE XVI. 
Development of Haemogregarina canis in the dog and in the tick 
Khipicephalus sanguineus. 
Fig. 1. Large oocyst from the tick. The nucleus of each sporocyst has multiplied till each 
possesses about 16. 
Fig. 2. Cyst from the spleen of a dog containing schizont with protoplasm filled with 
retractile spheres and six nuclei. 
Fig. 3. Cyst from the spleen of a dog containing three large merozoites and residual body. 
Fig. 4. Young schizont in mononuclear cell in spleen. The nucleus of the parasite 
discoloured to show the karyosome. 
Fig. 5. Schizont from spleen of dog. The nuclei show the karyosomes clearly. 
Fig. 6. Cyst from spleen of dog similar to that at fig. 3 but more discoloured. The nuclei 
of the merozoites consist of a nuclear membrane over which fine granules are 
scattered. There is a central karyosome. 
Fig. 7. Sporocyst from an oocyst in the tick. It shows the budding off of the sporozoites. 
Eight are formed at each pole. The drawing only shows four of these. 
Fig. 8. Cyst from spleen of dog. The small forms are destined to enter the leucocytes 
and to appear in the peripheral circulation. 
Fig. 9. First nuclear division of schizont in spleen of dog. The karyosome divides and 
functions as an intranuclear division centre. 
Fig. 10. Sporocyst from an oocyst in the tick. It shows the eight nuclei arranged at one 
pole. Eight nuclei were similarly arranged at the other pole. 
Fig. 11. Developing form in the tick. Possibly an early oocyst. 
Fig. 12. A sporozoite from a sporocyst in the tick. Length 14 g. 
Fig. 13. Early schizont in spleen of dog. The nucleus shows the karyosome. 
Fig. 14. Schizont from spleen of dog. Each nucleus has a karyosome. 
Fig. 15. A form within an epithelium cell of the gut of the tick. Possibly a zygote. 
Fig. 16. Large oocyst filled with sporocysts containing sporozoites from body of tick. 
Fig. 17. Developing sporoblasts in oocyst from the tick. 
