162 The Botanical Gazette. (May, 
Inoculation experiments. 
‘During the month of April, 1892, an experiment was putin 
progress to determine the relation of this organism to the o- 
ientation of the tubercles. Vetch seeds which had beet 
gathered the previous year for this purpose were planted intwo 
different vessels. These vessels contained sand from which 
the soil had been washed. The sand was saturated with dix 
tilled water to which was added a small quantity of kainite 
and acid phosphate, and the vessels were then steam sterilize! 
two hours a day for three successive days. The sand was 90 
saturated with water that it was covered with a thin layer 
This was necessary in order to provide sufficient moisture for 3 
the hard dry vetch seed to germinate. After the plants haé 
attained a length of 5™ to 10™, organisms from the culture 
tubes of vetch nutrient agar were transplanted to vessel no. 
1. An attempt was at first made with afine needle to moe 
late roots at certain points but the quantity of moisture in the 
sand quickly dispersed the organism over all parts © ©" 
surface of the sand. Vessel no. 2 was held as 2 MS" 
There were from fifteen to twenty plants in each vessel. 
During a period of a month the plants in both vessels made 
ory, and & 
® 
the organism within extended over a month's time,. 
was found at the close of this period that only 4 is 
plants in vessel no. 1 escaped inoculation. In ¥ 
hot a single tubercle was developed. a 
| 2 Jely of the same season 2 second inoculation exP 
_ Was conducted, the vetch plants this time being : 
Water culture. Five glass vessels, capacity about iv , 
having a rather small neck, were fitted each with a ook 
would float on the water when this rose above the ® 
vessel and partly filled the basin formed by the flaring 
and 
of 
