. ACTINOMYCOSIS. 433- 



and in either case mounted in glycerine. But althougli the fungus- 

 can be detected without any staining process, there may sometimes 

 be doubtful appearances, and then cover-glass prepai'ations should be- 

 made and stained by the method of Gram with eosin. The filaments 

 can be readily recognised, and this is of great value, as it forms 

 an additional means for the diagnosis of the disease. In combination 

 with orange-rubin we have a test that is as characteristic and useful 

 as staining for tubercle bacilli. The discharge, scraping from a 

 growth, sputum, or the isolated fungus is squeezed between two- 

 cover-glasses, which are then slid apart ; they are allowed to dry, 

 passed through the flame in the ordinary manner, and then stained 

 The cover-glasses can be cleared in clove-oil, the excess of clove-oi] 

 being removed by gentle pressure between pieces of blotting-paper, 

 and then the preparation can be mounted in balsam and rendered per- 

 manent. On examination of these specimens the masses of filaments- 

 will be found to be stained blue, and the tissue elements pink. These 

 filaments vary very much in extent and character in different pre- 

 parations. In some cases there are masses of short threads, which 

 are either straight, sinuous, or twisted, and branched. In other- 

 parts the field is occupied by very short, straight, or curved and 

 sometimes spiral fragments ; in others, again, there are comparatively 

 long strands. On examination with a high power, and with careful 

 illumination, some filaments will be observed to be momliform,. 

 while others are provided with a terminal oval body. There are 

 ■also free spherical, and oval, bodies stained blue, which represent the- 

 spores of the organism. When orange-rubin is used instead of 

 eosin, the clubs will be stained and easily recognised. This method 

 enables one to determine the exact relation of the threads to the- 

 club-shaped bodies ; and this is an interesting point, as it has been 

 suggested that the threads are not connected with the clubs, but are 

 merely an adventitious micro-organism growing in the track of the 

 ray-fungus. The threads are stained blue and the clubs crimson. 

 In the younger clubs the protoplasm of the thread can be traced into 

 the interior of the club. In some of the older clubs the central 

 portion takes a yellowish stain, and in others the protoplasm is not 

 continued as a thread, but is collected into a spherical, ovoid, or 

 pear-shaped mass. In others again, irregular grains, stained blue, are 

 scattered throughout the central portion. The sheath of the thread 

 is stained pink ; and the protoplasm, stained blue, fills the sheath, or- 

 consists of small spherical or irregular grains, giving a distinctly 

 headed appearance. 



The effect of various reagents should be tried upon the isolated 



28 



