14 
Colorado Experiment Station 
culture from a diseased leaf blade, were used in this experiment. 
Each of nine pea vines, approximately 15 centimeters in height, was 
inoculated with one of these cultures; the germs were introduced 
hy needle pricks both in the stems and in the leaves. The plants 
were kept covered with bell jars for 48 hours and sprayed with 
sterile distilled water at frequent intervals; at the end of this time 
they were placed in the greenhouse. 
Observaitions 
Dec. 21 , ip/ 5 .—All of the inoculations on the stems seem to 
have taken nicely, as they show watery, slightly sunken areas around 
the needle pricks. 
Dec. 22 , ipij .—The watery zone around the needle punctures 
more pronounced than the day before; many O'f the leaves are 
beginning to show watery spots. 
Jtui. 5 , ipi6 .—While we are obtaining positive results un¬ 
questionably with all nine cultures, two of them seem tO' be somewhat 
more virulent than the others, as the disease is progressing more 
rapidly in the two plants inoculated with these particular strains. 
The watery spots encircling the needle punctures have coalesced 
into continuous dark olive-green lesions extending over the in¬ 
oculated portion of the stems. All appear practically the same, but 
the area involved is considerably greater in the two cases mentioned 
above. Some of the leaves are shrivelled, others show watery spots 
and irregular yellow blotches; growth seemis to be checked. 
.Ian. y/, jpi6 .—iThe inoculated shoots on all nine plants are 
dead and black; three of the plants have thrown out a single new 
shoot from below and three have responded with two new shoots; 
three died without producing any new growth at all. Fig. II is a 
photograph, taken at this time, of the two plants with the two 
new shoots; note in each case the dried, inoculated, dead vine 
between the two healthy ones. A third check plant is in the 
same pot. 
Inoculations of January 6 , 1916 .— Horsford Peas 
The two cultures which appeared to be the most virulent in 
the preceding series, and which produced the most typical symp¬ 
toms of disease in the host were selected for reinoculation in the 
present experiment. For convenience, these may be designated as 
Numbers 3 and 8 . 
Four plants, 7 cm. in height, were inoculated with Culture 
3 by means of single needle pricks in a line along the stem. Three 
similar plants were likewise inoculated with Culture 8 ; 72 -hour 
agar cultures were used in both cases. One check plant was left 
