MORPHOLOGY OF TUBERCLE BACILLUS. 239 



they are comparatively thin organisms (Figs. 87 and 88). 



Sometimes, however, longer forms, up to 5 /:i or more in length, 



are met with, both in cultures . ^ 



and in the tissues. They are ' ' ,^ --v, 



straight or slightly curved, and ^ ^ ' ^ 



are of uniform thickness, or may 



extremities. When stained they -i 'y» ^ ^•^vV W "^ 

 appear uniformly coloured, or ; f^ y t '"^'"^'C •>. /^''"^"C'' 



may present small uncoloured ' r- s ■' \^^ -7— v 



( 



show slight swelling at their /* •y^ / i. \>j / 



may present small uncoloured ' ^^ 



spots along their course, with yij'\ ^^ 1 



darkly stained parts between. , j — »' V' \ 



In the case of the tubercle ba- x ^ 



cillus, as of many other organ- ""'■ 



isms, a considerable amount of fig. s/.-Tuberde baciiii, from a pure 



discussion has taken place as culture on glycerin agar. 



Stained with carbol-fuchsin. X 1000. 



to the occurrence of spores. 



In such a minute organism it is extremely difficult to recog- 

 nise the exact characters of the unstained points. Accordingly, 



we find that 

 some consider 

 these to be 

 spores, while 

 others find that 

 it is impossible 

 to stain them 

 by any means 

 whatever, and 

 consider that 

 they are really 

 of the nature 

 of vacuoles. 

 Against their 

 being spores is 

 also the fact 

 that many oc- 

 cur in one ba- 



FlG. 88. — Tubercle bacilli in phthisical sputum ; they are longer 

 than is often the case. Film preparation, stained with carbol-fuchsin CUIUS. t^tuerS 

 and methylene-blue. X looo. acrnill hold that 



some of the condensed and highly stained particles are spores. 



