8 



Dr. H. L. Duke. 



[Dec. 19, 



impossible to decide which experiment actually caused the infection, though 

 some evidence on this point may he gathered from Table II. 



Dissection of the Positive Flies of the above Experiments. 

 All positive flies were examined by Miss Eobertson, and an account of the 

 morphology of the flagellates will appear in due course in her report. I have 

 here to express my obligation for information regarding the parts of the 

 alimentary tract infected, with which Miss Eobertson has supplied me 

 throughout. 



In the following Table II the flies are arranged in a progressive series, 

 according to their age when dissected, all the flies used being newly hatched 

 at the commencement of the experiment. The " + " and " — " signs are 

 used to indicate presence or absence of flagellates in the various regions of 

 the alimentary canal, and the intensity of an infection is indicated by 

 repetition of the " + " sign. The symbol " " denotes that no observations 

 were recorded concerning that portion of the gut : — 



Table II. 













Eegion of gut. 





Date. 



No. of 



fly. 



Age of 

 fly when 

 dissected. 



No. of 

 nient. 



Sex. 



Hind 



Thoracic 

 junction 





Salivary 



Proboscis. 



Injection into 

 G-oat 329. 













gut. 



proven- 

 triculus. 



triculus. 



glands. 





1.8.11 



i 



11th day 



213 



? 



+ + 













17.8.11 



2 



14th „ 



243 



? 



+ + 



+ + + 











25.8.11 



3 



22nd „ 



243 



? 



+ + + 













28.8.11 



4 



25th „ 



243 



? 



+ + + 



+ + + 



+ + + 





+ + + 



Contents of proven- 

 triculus injected 

 into Goat 329. „ 



29.8.11 



5 



26th „ 



243 



? 



+ + + 



+ + 



+ 









5.9.11 



6 



33rd „ 



243 



? 



+ + + 



+ + + 













18.9.11 



7 



46th „ 



243 



S 



+ + + 







+ 









20.9.11 



8 



48th „ 



243 



s 



+ + + 















20.9.11 



9 



48th „ 



243 



¥ 



+ + 













27.9.11 



















\ f 



Proventriculus of 



10 



58th „ 



235 





+ + + 



+ + + 



+ + + 







each of these flies 



27.9.11 



11 



58th „ 



235 



¥ 



+ + + 



+ + + 



+ + + 







_ \ 



injected subcutane- 



27.9.11 



















I 



ously into Goat 329. 



12 



58th „ 



235 



? 



+ + + 















27.9.11 



13 



58th „ 



235 



¥ 



+ + + 



+ + 



+ + + 







+ + 





5.10.11 



14 



64th „ 



238 



¥ 



+ + + 



+ + + 



+ + 









9.10.11 



15 



67th „ 



243 



<? 



+ + + 













Note. — Goat 329, \mder examination 56 days, has never shown trypanosome 



