S. R. Christophers 
43 
2. Nymphs fed on dogs free from haemogregarines. 
26. 8. 07. Nymphs fed on dog 22 (uninfected). 
6 examined showed nothing. , 
3. 9. 07. Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 22 (uninfected). 
8 examined very thoroughly. All negative. 
4. 9. 07. 6 more of the same nymphs examined about 24 hours after 
dropping. All negative. 
6. 9. 07. Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 29 (uninfected). 
6 examined very thoroughly. All negative. 
12. 9. 07. Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 33 (uninfected). 
16 examined very thoroughly. All negative. 
13. 9. 07. 12 more of the same nymphs 24 hours after dropping examined 
very carefully. All negative. 
3. 
Nymphs fed on dogs whose blood contained haemogregarines. 
3. 9. 07. 
3. 9. 07. 
4. 9. 07. 
6. 9. 07. 
10. 9. 07. 
11. 9. 07. 
Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 23 (fair number of haemogregarines). 
8 examined. All showed vermicules but one. In three vermicules 
were fairly numerous, in four they were scanty. 
Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 24 (numerous haemogregarines). 
15 examined. All showed vermicules. 
6 more nymphs from dog 24 about 24 hours after dropping. All 
showed vermicules. 
Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 24 (numerous haemogregarines). Same batch as fed with 
negative results on the same day on dog 29 (uninfected). 
14 examined. All showed vermicules. 
Nymphs fed as larvae on dog 21 (uninfected) and as nymphs on 
dog 40 (haemogregarines). 
4 examined. All showed vermicules. 
7 more nymphs of same batch 24 hours after dropping. All 
showed developing vermicules. 
4. Unfed adults fed as larvae and nymphs on uninfected dogs. 
28. 8. 07. Adults fed as nymphs on dog 10 (uninfected). 
12 dissected showed no cysts. 
11. 9. 07. Adults fed as larvae on dog 12 (uninfected) and as nymphs on 
dog 21 (uninfected). 
6 dissected showed no cysts. 
3. Unfed adults fed as larvae on uninfected dogs and as nymphs on infected dogs. 
16. 8. 07. Nymphs fed on dog 11 (numerous haemogregarines). 
9 dissected on moulting. All showed numerous cysts approaching 
maturation. 
Numerous other experiments not recorded showed that cysts in 
this stage were always to be obtained if the ticks had been 
fed as nymphs on heavily infected dogs. 
