ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 



247 



on which the apparatus rests. The steam rises into the upper inverted 

 cone, in the hollow of which rests the glass filter funnel. The inner 

 wall of this hollow cone is perforated to permit of the escape of the 

 steam and its access to the outside of the glass funnel. Any condensa- 

 tion water trickles down into the receptacle below, seen in the hollow 

 of the Bunsen ring. 



Fig. 35. 



Examination of the Blood for Trypanosomes, etc.* — C. Levaditi 

 and V. Stanesco have utilised the hasmagglutinating property of ricin 

 to facilitate searching in the blood for trypanosomes, spirilla, and the 

 like. They take small centrifuge tubes and place 4 c.cm. of the solution 

 of ricin in each tube. The tubes are then sealed and sterilised. When 

 required for use, a tube is opened and 20-30 drops of blood introduced. 

 Agglutination begins at once, and is completed in a few minutes. 

 When all the globules have fallen to the bottom, the supernatant fluid 

 is decanted and centrifugalised. The supernatant fluid is again centri- 

 fugalised, leaving a drop to dilute the sediment. This is then pipetted 

 off, and may be examined fresh or stained with Giemsa. In the 



* C.R. Soc. Biol. Paris, lxvii. (1909) (1909) pp. 594-6. 



