356 



MICRO-ORGANISMS AND DISEASE [chap. 



Now, if the tubercle bacilli had no spores, they would 

 not in all cases survive thorough drying ; no sporeless 

 bacillus is known that can survive thorough drying ; 

 whereas all bacilli in the stage of spore-bearing survi-\'e this 



Fig. 139. — From the same Kidn'ey as in preceding figure. 



a. L.iri;c arter\- filled \\ith caseous matter, and in it numerous tubercle-bacilli. 

 /'. Coat of artery. 



c. Nuclei of the tuberculous new growth, d. A Malpighian corpuscle. 



Magnifying power about 500. 



process. Further, tubercular matter and cultures of tubercle 

 bacilli survive temperatures up to loo" C. Non-spore- 

 bearing bacilli and micrococci are killed by being exposed 

 for five minutes to a temperature of 60-70 C., whereas 



