INFECTION-POWERS OF ASCOSPORES IN ERYSIPHACE®. 168 
In the next experiment (Exper. no. 8) ascospores were sown on 
March 81st, on barley and rye. Seedling plants were used, twelve 
days old. Three leaves of the barley were inoculated. il 
two of the oe . leaves bore each a patch of mycelium with 
ene conidiophores; on one cont rol leaf there was also a similar 
conidia. By Apri 13th these Oidium op bore sses 
spores, and secondary infection w ace on several of 
the young leaves which had appeared during the 
ages and which now bore mi sof mycelium. Two 
leave he were inoculated, but neither these nor any of 
the contol leaves showed any signs of infection throughout the 
experim 
In ‘ie next experiment (Exper, no. 4), on the same date, seed- 
lings newts days old of wheat, barley, and oats were inoculated— 
three leaves in each case. With re regard to the barley, one inoculated 
leaf bore, on April 6th, a small patch of mycelial hyphe. On 
April 7th two of the inoculated leaves bore minute flecks of myce- 
ose the inoculated leaves, y 
have rubbed against it. On April 8th two of the imbialalad leaves 
bore each a patch of mycelium with groups of young conidiophores; 
on the third inoculated leaf a small patch of mycelial hyphe had 
appeared. On April 11th two of the inoculated leaves bore each a 
patch of Oidiwm with dense powdery masses of spores, and one bore 
also another smaller patch of myceliu um with nearly ripe conidio- 
ur 
the ascospores had — sown. The third inoculated leaf bore a 
lium on the one pater leaf now bore a powdery mass of spores. 
On April 16th all the inoculated leaves ie numerous patches of 
Oidium with very powdery masses of spon which dispersed in a 
cloud on the leaves being touched. No trace of any infection ap- 
peared on the wheat and barley _— car course of ie Aaya 
n Exper. no. 5 ascospores wer own, on Apri 
seedlings of barley and wheat (kdrirtoen have ola) mii of rye inane 
one days old). Three leaves were inoculated in each case. 
regard to the barley, on April 6th a small fleck of mycelial hyphe 
was observable on one of the inoculated leaves. On April 7th two 
infected ; one leaf bore two patches, one with a powdery mass of 
ff in a cloud on the leaf being saeaked, “the 
4 
2 6th all the three infected Re bore 
conidio at vat On April 16t on 
each 2-3 Oidi: tches with powdery masses of conidia. 
fully ripe or old 7 cinta soon. the mass, were of pale rosy tinge 
