122 PROTISTS AND DISEASE 



be pleasing to the eye : two pairs of Petri dishes and two 

 watch-glasses being all that is required besides the micro- 

 scope, slides and covers, mounted needles, wire loop, &c. 

 which already find their places. 



The patient's skin should be cleansed with ether and 

 absolute alcohol, no strong antiseptic being used. Water 

 should be taken after the tap has been allowed to run a few 

 seconds, in order to remove traces of copper, and boiled, as 

 also should all watch-glasses, Petri dishes, slides, &c. 



A watch-glass is placed in the lower of each pair of dishes 

 and some water (not enough to float or cover the watch- 

 glass) is poured into the lower dish, Fig. 28. One dish is left 

 covered by its upper half ; into the watch-glass of the other 

 is placed a little heap of excised lesions cut open from the 

 surface downwards ; or of the white wax-like material 

 squeezed out of ripe lesions. For small portions a cupped 

 slide may replace the watch-glass. A few drops of water, 

 but not enough to cover the heap, are now added and the 

 upper half of the dish is placed over the lower. Rain- 

 water might suit better than tap-water. Streaming occurs 

 with normal saline, and the addition of a trace of bicarbonate 

 of soda to the latter favours subdivision of the bodies into 

 segments. 



The cultures must be kept at room-temperature. 



