l6o BACTERIA IN RELATION TO PLANT DISEASES. 



It grew slowly or not at all in peptone water with i per cent potassium nitrate. In 

 one tube, which clouded, no nitrite was detected in 13 days. It grew slowly in a mixture 

 of grass broth, cane-sugar water, and peptone nitrate water, clouding the fluid, but there 

 was no production of nitrite (9 days). Doubtful growth in Dactylis broth with i per cent 

 peptone (10 days). There was no growth in potato broth with i per cent potassium 

 nitrate. Subsequently in fermentation tubes of peptone bouillion with i per cent potas- 

 sium nitrate there was no reduction of the nitrate (17 days). When tested the tubes were 

 clear in the closed end, well-clouded in the open end, with an ample yellow precipitate 

 and no pellicle. There was very slow growth during the first week. The check tube 

 gave a bright blue reaction with diphenylamin. 



In first 1 1 days (at 26 C.) no change in milk except the formation of a narrow yellow 

 rim. In litmus milk no change during first week, then (i i days) slightly bluer than check. 



On nutrient gelatin at the end of 19 days at 20 C. there was a distinct pale yellow 

 surface growth, colony-form, with some buried colonies. No liquefaction for some weeks; 

 at end of 7 weeks 5 mm. liquefied ; at end of 5 months about one-third liquefied. 



I have named this organism Aplanobacter rathayi in honor of the late Emerich Rathay 

 (Science) . It is related to Aplanobacter michiganense perhaps too closely, but so far inocula- 

 tions into tomato have yielded only negative results (see p. 165). 



It is a yellow non-flagellate rod with bluntly rounded ends, and on the plant is about 

 twice as long as broad, measuring when stained withcarbol fuchsin 0.6 to 0.75 X 0.75^ to 

 i.5M- On culture media (2-day potato) stained with carbol fuchsin, they measure 0.5 to 

 O-75/i Xo.gs to 1.3/1- It occurs most frequently singly or in pairs joined end to end. 

 Capsules occur (fig. 7ig). It grows in milk with formation of a yellow rim, but no 

 visible change in color or consistency (n days); subsequently the rim widened and a 

 large amount of chrome yellow precipitate formed and there was separation of the casein. 

 Litmus milk is slowly blued : subsequently (4 months) the milk became a uniform purplish 

 and occasionally there was some reduction of the color (pi. 23). Nitrates are not reduced. 



It does not grow in Cohn's solution. Grape sugar is split and acid is formed, but 

 not gas. It grows slowly on nutrient agar and gelatin, and in other culture media such as 

 peptone water with potassium nitrate, milk, and litmus milk; in milk it makes a long-con- 

 tinued and very copious yellow growth.* Saccharose and lactose are fermented slowly. 



On agar plates some strains of the organism grow only when sown thickly or when 

 cultivated with the associated white organism (pi. nB). Curiously the yellow colonies 

 appeared only on the buried white colonies, not on the surface ones. 



The organism is undoubtedly diseminated on the seeds. It retains its vitality on 

 dried spikelets for a long time, probably a year or more, judging from the fact that it grew 

 readily in our tests at end of 7, 9, 10 and 1 1 months To insure growth inoculation into most 

 media must be heavy. Group No. 21 1.2222522. 



LITERATURE. 



1899. RATHAY, EMERICH. Uebcr eine Bakteriose von Dactylis glomerata L. Sitz. Ber. der Wiener Akad. i Abth. 



Bd. cvni, pp. 597-602. 

 Also a separate. 



1913. SMITH, ERWIN F. A New Type of Bacterial Disease. Science. N. S., Vol. XXXVIII, No. 991, Dec. 26, 1913, 

 p. 926. 



After the above was in type the writer visited Klosterneuberg and through the courtesy of Dr. Linsbauer, Director 

 of the Lehr-Anstalt, had opportunity to examine 1.5 jars of alcoholic material left by Rathay, and to satisfy himself 

 that the Austrian disease is identical with the Danish (see figs. 716, c, and h, made from this material). Rathay's 

 manuscript was not left in the Lehr-Anstalt but in his house, where it came into possession of one of his daughters, 

 who finally destroyed it as valueless. From this sacrifice to the goddess of good-housekeeping there escaped only some 

 photographs and drawings which I had hoped might be reproduced here and to that extent help to keep alive the 

 memory of a brilliant man called away too early from the scene of his activities. They were promised but not received. 



That this disease still occurs on the Kahlenberg is shown by the fact that I collected it there myself (Nov. 2,1913) 

 in the oak woods on the east side of the railroad track, a few hundred yards below the uppermost station. Moved 

 to a hot house in Washington, one of these diseased plants produced 15 flowering shoots in 1914, all of which were 

 healthy. 



