ANIMAL PARASITES INOCULATED INTO PLANTS. 177 



those forms that are natural parasites of certain higher vegetable species showed no power to spread in 

 plants which were not their natural hosts, but they were able to live at inoculation-point for a con- 

 siderable time. * * * 



"The distribution of the micro-organisms in the plant-axis, as determined by culture experiments, 

 always took place in an ascending direction. This distance varied from 30 to 50 mm. from point of 

 introduction, but in no case were bacteria found more than 2 to 3 mm. below inoculation-point." 



Charrin (1893) injected Bad. pyocyaneum into Pachyphyton bracteosum, a plant of the 

 family Crassulaceae. The inoculations were made into the fleshy leaves. This organism 

 lived for some time and multiplied (mostly in the intercellular spaces). The leaves of the 

 plant, after the germs had grown in them 15 to 30 days, became wrinkled, lost color, and 

 fell off; the acidity of the leaves lessened in proportion as the bacteria multiplied. Even 

 when large numbers of the organism were introduced (0.25 to 0.5 cc. of a liquid culture) 

 it remained alive a short time only (2 to 3 weeks, more or less) and when only r to 2 drops 

 were inoculated 8 to 1 2 days usually sufficed to kill the organism, especially if a weakened 

 germ was used. 



An interesting paper, especially the last half dozen paragraphs on immunity. 



Kasparek and Kornauth (1896) experimented with Aplanobacter anthracis on oats, 

 barley, wheat, rape and maize. Their method of procedure was as follows: 



Sterilized flower-pots were filled half full of sterile soil and each watered with 10 cc. of bouillon 

 containing large numbers of spores and threads of the anthrax organism. Sterile seeds of the above 

 mentioned plants were then embedded in this moistened earth and the pot filled nearly full with 

 additional sterile soil. The surface of the seeds was sterilized by soaking for a short time in 2 per 

 cent mercuric chloride solution which was removed by washing in sterile water, alcohol and ether. 

 Then they were put for 24 hours into nutrient bouillon at blood temperature to be sure that their 

 surface was actually sterile, and the seeds in those tubes which clouded were rejected. The germi- 

 nating power of seeds thus treated was not injured. After two months in the first series, and after 

 three months in the second series the experiment was broken off and the earth and plants examined 

 microscopically and bacteriologically. A microscopic examination of the soil showed that anthrax 

 spores were abundant not only in the part which was watered, but also in the upper layers of the 

 soil even to the surface, but no anthrax threads or rods could be found. Samples of this soil pro- 

 duced typical anthrax when inoculated into white mice and also gave numerous anthrax colonies 

 when sowed in plate cultures. The unwashed underground parts when inoculated into mice also 

 produced typical anthrax, but when these roots and stems were first washed with mercuric chloride, 

 alcohol and ether, the same as the seeds had been, they did not produce any disease in mice when 

 inoculated, and the agar plates also remained sterile. Moreover, a microscopic examination of sec- 

 tions made through the roots and other parts of these plants grown in anthrax infected earth likewise 

 showed complete absence of the anthrax organism in the tissues of the plants. 



Kornauth (1896) continued and extended these experiments, including Streptococcus 

 pyogenes with anthrax in order to have a very small Schizomycete for comparison with the 

 large one. 



The results were the same. Kornauth used for his experiments seeds of maize and peas. These 

 were washed in 2 per cent mercuric chloride water, alcohol, and ether, then put into sterile bouillon 

 in Petri dishes and incubated for 2 days at 37 C. If the bouillon remained clear then it was inocu- 

 lated with either A planobacter anthracis or the streptococcus. The cultures succeeded admirably and 

 appeared on microscopic examination to be pure. After about 3 weeks when the seedlings had 

 reached the length of about 2 cm. the experiment was broken off. After washing the seedlings in 

 mercuric chloride water, alcohol and ether to render the surface sterile, they were crushed with anti- 

 septic cautions, and inoculated into mice (those used with anthrax) and also put into sterile bouillon. 

 Sections of these seedlings were also prepared for microscopic examination. The result of the experi- 

 ment was that the mice did not contract the disease, the bouillon remained clear, and the sections 

 showed no trace of any bacteria. 



His conclusion, therefore, is that the plant under normal conditions is a perfect filter for bacteria, 

 that only a few species of bacteria can penetrate the uninjured plant tissue, and these only under 

 very special conditions. He next undertook to determine whether the organisms would multiply 

 in injured tissue, i.e., in wounds, as stated by Lominsky. For this purpose he selected the following 



