ADDENDUM. 



The following observations were made too late for insertion in the body of the text: 



(1) Aplanobacter michiganense vs. Apl. rathayi. Both liquefy gelatin slowly, but the 

 latter liquefies the more rapidly and the surface growth (streak) floats about in the nearly 

 clear fluid as a twisted ribbon. Apl. michiganense, on the contrary, clouds the fluid. 



(2) Peanut wilt. In June, 1914, we obtained bacterial wilt of peanuts using both 

 Medan III and Florida potato (isolation of 1914). Inoculations were by needle pricks on 

 stems ; the time between inoculation and appearance of disease was about two weeks ; great 

 numbers of bacteria were seen in the tissues. Subsequently the wilt of peanut was also 

 obtained by inoculating from a pure culture of the Creedmore, N. C., tobacco organism. 



(3) Tobacco wilt. This was obtained in June, 1914, using Florida potato (1914), 

 Florida tobacco (1914) and Creedmore, N. C., tobacco (1914). The inoculations were by 

 needle pricks from pure cultures (subcultures from poured-plate colonies) on stems and 

 leaves. The time between inoculation and appearance of disease was about 4 to 10 days. 



(4) Bact. solanacearum Effect of drying. On cover slips Medan III and Florida 

 potato (1914) were dead at the end of 6 to 9 days, i. e., refused to grow when thrown into 

 peptone-beef bouillon. These cover slips were wetted from young peptone water cultures 

 and were kept in the dark in a covered Petri-dish at room temperatures (of June). Sub- 

 sequently tests with the Creedmore tobacco organism (1914) and the Florida tobacco 

 organism (1914) showed all dead on the 6th day or earlier. The tests were begun on the 

 5th day, at which time the organism was alive on a few of the cover glasses, i. e., i out of 8 

 in Creedmore and 2 out of 8 in Florida. Tests on the 6th, 7th, and gth days showed all 

 dead. The covers (64 in all) were wet from cloudy 24-hour-old peptone water cultures 

 and kept in the dark, in sterile Petri-dishes, in the well ventilated laboratory at room 

 temperatures (of July). The covers were thrown into tubes of + 14 peptone bouillon. 



(5) Bacterium solanacearum in litmus milk-\-cream. Medan III always reddens this 

 medium. It may therefore be known as var. Asiaticum nov. var. None of the American 

 isolations of 1914 (Florida potato, Florida tobacco, and Creedmore tobacco) have done so. 

 (Experiments continued 4 to 8 weeks, using subcultures from 15 colonies.) 



(6) Bacterium solanacearum in Meyer's solution + Am. lactate. With Medan III and 

 Florida potato (1914) at the end of 4 weeks there had been no growth. 



(7) Bacterium solanacearum in Meyer's solution -\- Asparagin. At the end of 4 weeks, 

 4 of the 8 tubes of Medan III clouded. All of the Florida potato (1914) remained clear. 



(8) Bacterium solanacearum in Meyer's solution + KNOs + Sodium acetate; 



Do. Do. Do. + Sodium lactate. 



Do. Do. Do. + Sodium butyrate. 



Neither Medan I II nor Florida potato (1914) would grow in these media. Testof 4weeks. 



(9) Bact. solanacearum inoculated on Livingston's Dwarf Aristocrat tomato. On page 

 189 (exp. of 1905) the statement is made that of many varieties tested the above named 

 was most susceptible. Fearing this might be an accident, the experiments were repeated in 

 July, 1914, using four strains of the bacteria: Medan III, Florida potato (1914), Florida 

 tobacco (1914), and Creedmore tobacco (1914). In all 24 plants were inoculated, 6 from 

 each strain. All except Medan III were wilting or wilted on the third day with enormous 

 multiplication of bacteria in the tissues. The inoculations were made on young plants 

 showing two good leaves (besides the cotyledons) and four when collected. The pricks 

 were made with a fine needle ; most of the punctures were made on petioles. Older plants 

 were not available. The check plants remained sound. These plants contained 93 per 

 cent of water. This experiment was repeated a few days later with similar results. 



(10) Loss of Virulence. Medan III, lost much of its virulence during 12 months culti- 

 vation in the laboratory without reinoculation into plants, i. e., then it was less active on 

 tobacco and on tomato than the recent (1914) isolations from American sources (PI. 45). 



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