1910.] Trypanosoma lewisi by the Rat-Jlea. 



279 



were first seen in its blood. Smears were made daily of the blood until 

 15/12/09, at which date the multiplication-period came to an end. 

 6/12/09. — Eat C 3 was removed from Cage C, was carefully freed from fleas, and was put 

 into a fresh cage by itself. 2 fleas recovered from it were put back into Cage C. 

 A healthy, clean tame rat (C4) was tlien put into Cage C. 



Rat C 3 was examined daily from 6/12/09 until 11/12/09, and again on 

 13/12/09, when trypanosomes wei e first seen in its blood. Permanent smears 

 of its blood were made daily from 13/12/09 till 18/12/09, when the multipli- 

 cation-period ended. 



8/12/09. — Rat C 4 was removed from Cage C, was carefully fi'eed from fleas, and was 

 then put into a separate cage by itself. 3 fleas recovered from it were put back 

 into Cage C. A healthy, clean tame rat (Rat C 5) was then put into Cage C. 



Rat C4 was examined daily from 8/12/09 to 11/12/09, and again on 

 13/12/09, when trypanosomes were first found in its blood. Permanent smears 

 were made daily of its blood from 13/12/09 till 18/12/09, when the multiplica- 

 tion-period had practically ended. 

 10/12/09. — Eat C5 was removed from Cage C, was carefully freed from fleas, and was 

 then put into a fresh cage by itself. 14 fleas recovered were put back into 

 Cage C. A healthy, clean tame rat (Rat C 6) was then put into Cage C. 



Rat C5 was examined regularly from 11/12/09 till 14/12/09, when trypano- 

 somes were first seen in the blood. Permanent smears were made of its 

 blood from 14/12/09 till 21/12/09, when the multiplication-period came to an 

 end. 



11/12/09. — Eat C6 was removed from Cage C, was carefully freed from fleas, and was 

 then put into a separate cage by itself. 20 fleas recovered from it wei'e put back 

 into Cage C. A healthy, clean tame rat (Rat C 7) was then put into Cage C. 



Rat C 6 was examined regularly from 13/12/09 till 16/12/09, when trypano- 

 somes were first found in its blood. Permanent smears of its blood were 

 made from 16/12/09 till 2.3/12/09, when the multiplication-period came to an 

 end. 



13/12/09. — Rat C 7 was removed from Cage C, was carefully freed from fleas, and was put 

 into a separate cage by itself. 16 fleas recovered from it were returned to 

 Cage C. A healthy, clean tame rat (Rat C 8) was then put into Cage C. 



Rat C7 was examined regularly from 15/12/09 till 17/12/09, when trypano- 

 somes were first seen in its blood. Permanent smears were made of its 

 blood from 17/12/09 till 24/12/09, when the multiplication-jjeriod came to an 

 end. 



15/12/09. — ^Rat C8 was removed from Cage C, was carefully freed from fleas, and was 

 put into a separate cage by itself. 5 fleas recovered from it were returned to 

 Cage C. A healthy, clean tame rat (Rat C 9) was then put into Cage C. 



Rat C 8 was examined regularly from 16/12/09 till 20/12/09, when trypano- 

 somes were first seen in its blood. Permanent smears were made fioni 

 20/12/09 till 26/12/09, when the multiplication-period came to an end. 

 17/12/09. — Rat C9 was removed from Cage C, was carefully freed from fleas, and was 

 put into a separate cage by itself. 23 fleas recovered from it were put back into 

 Cage C. A healthy, clean tame rat (Rat C 10) was then put into Cage C. 



Rat C9 was examined regularly from 18/12/09 till 21/12/09, when trypano- 

 somes were first seen in its blood. Permanent smears were made from 

 21/12/09 till it was found dead on 28/12/09. On this date the multiplication- 

 period had not quite ended, but from appearances would probably have ended 

 on the following day, 29/12/09 



