258 BACTERIA. 



within the large masses of protoplasm found in this 

 region. 



In the human subject the felted network, the cocci and 

 the bacilli are usually most numerous ; they are, in fact, 

 said to be typical of actinomyces in the human subject. 

 Here again the involution or club-forms are frequently 

 met with, especially in the pus that is discharged from 

 the abscesses of the lungs or of bone. The slimy pus 

 in these cases, however, appears to contain a considerable 

 proportion of the "mucine," that in cattle goes to form the 

 thickened sheaths above described. The process of evolution 

 of the "Ray' ; fungus is much the same in the human 

 subject as in the abnormal case already described as occurring 

 in the cow. 



It is interesting to note that most of the experiments 

 that have been made on the cultivation of this organ- 

 ism have been attended with complete failure a failure 

 that in some measure, at any rate, appears to be due to 

 to the fact that almost all experimenters have used for their 

 inoculating material only those colonies in which the club- 

 shaped organisms have become well developed. The first 

 attempt that was at all successful was made by Bostrom, 

 who, throwing aside the club-like processes, took for his 

 inoculating material the central network, selecting as far as 

 possible young growing colonies for his seed material. His 

 method of procedure was as follows : With the utmost 

 care he removed small colonies, which were at once in- 

 troduced into sterilized gelatine, with which a " plate " 

 cultivation was made. After a few days any points that 

 were found to be pure, z>., around which other organ- 

 isms were not growing, were removed from the gelatine 

 with a sterilized platinum needle, and were crushed be- 

 tween sterilized glass plates ; with the platinum needle, 

 stroke cultivations were made on ox blood serum, and 

 agar-agar. A finely granular growth first made its appear- 

 ance along the line of inoculation ; this gradually became 

 more marked, then small yellowish red nodules were seen, 

 around which delicate branched processes spread out ; these 

 yellowish masses soon began to run together, and at the end 

 of seven or eight days were covered with a delicate fluffy 

 white layer. This growth apparently went on best at the 

 temperature of the body, and on microscopic examination 



