968 THE HIGHER BACTERIA, MOLDS AND FUNGI 



animal serum or whole blood has been added. In cultures from 

 media to which no animal fluids have been added, such as glucose 

 agar or gelatin, no clubs are found. In preparations stained by 

 Gram's method the clubs give up the gentian-violet and take counter- 

 stains, such as eosin. 



The coccus-like bodies found Occasionally lying between the fila- 

 ments of the central mass, most observers now agree, do not 

 represent anything comparable to the spores of the true hyphomy- 

 cetes. In many cases they are unquestionably contaminating cocci ; 

 in others again they may represent the results of degeneration of 

 the threads. 



In tissue sections, the microorganisms may be demonstrated by 

 Gram's method of staining or by a special method devised by 

 Mallory. 23 This is as follows for paraffin sections : 



1. Stain in saturated aqueous eosin ten minutes. 



2. Wash in water. 



3. Anilin gentian-violet, five minutes. 



4. Wash with normal salt solution. 



5. Gram's iodin solution one minute. 



6. Wash in water and blot. 



7. Cover with anilin oil until section is clear. 



8. Xylol, several changes. 



9. Mount in balsam. 



Cultivation. The isolation of actinomyces from lesions may be 

 easy or difficult according to whether the pus is free from con- 

 tamination or whether it contains large numbers of other bacteria. 

 In the latter case it may be almost impossible to obtain cultures. 

 The descriptions of methods of isolation and of cultural character- 

 istics given by various writers have shown considerable differences. 

 The most extensive cultural work has been done by Bostroem, 24 

 Wolff and Israel, and by J. H. Wright, Bostroem has described his 

 cultures as aerobic, but Wolff and Israel 25 and Wright 26 agree in 

 finding that the microorganisms isolated by them from actinomycotic 

 lesions grow but sparsely under aerobic conditions and favor an 



:3 Mallory, Method No. 1, Mallory and Wright, "Path. Technique/' Phila. 

 1908. 



24 Bostroem, Beitr. z. path. Anat. u. z. allg. Path., ix, 1890. 



25 Wolff und Israel, Virch. Arch., 1891, cxxvi, 4. 

 M J. H. Wright, Jour. Mod. Res., viii, 1905. 



