162 THE JOURNAL OF BOTANY 
water, and Harper (6) later has remarked, with regard to Sphero- 
theca Castagnei and Erysiphe communis: ‘ Die Zellen der Innenwand 
behalten noch in sehr oe panies tok ihren protoplasmatischen 
Inhalt und ihre Kerne. . . Es ist nicht unméglich, dass ihr Inhalt 
der ol erin zur Zeit der Entleerung der Ascen vermittelt.” 
The ing of the perithecium and the n aeiye td - the asco 
spores of E. “avaiiinis were recorded as far back as 1884 by Worth- 
ington Smith (7), but the observations here published have been 
generally oe This author recorded that if old grass or 
straw infected with Erysiphe is kept in damp air under a bell-glass, 
and strips of glass smeared with glycerine are suspended over the 
infected leaves, it will be found that <r asci and ascospores will be 
ejected on to them from the peritheci 
The little that has been hitherto known on the subject of the 
germination of the ascospores will be found given in my mono- 
graph, &c. (2, pp. 9,104), (8, p. 20). Wolff (8) has Sige ta a 
few observations on the germinatio n of the ascospores of F. ° 
nis, and of the infection of the leaf of a wheat-plant by a gonial: 
nating ascospore. The same author also makes the following in- 
en 
Graminis betrifft, so fand ich dieselbe auf Weizen, von denen nach 
ig kaa englische und gewohnliche Sorten, Sommer- 
d Wintervarietiten einen geeigneten Boden fiir sie a n; ein 
gue bgebe 
Gleiches war bei Roggen und Gerste der Fall; durchaus nie fand 
ich sie, und missgliickte jeder Kulturversuch auf Hafervarietiiten.” 
he object of my experiments was to ascertain what shies the | 
i e form of F. j 
minis 
re) 
se Gi archal to conbibata in the eonidial stage a sharply defined 
4 ‘biologic form.” The fo ollowing method of inoculation was used in 
all the experiments. At the time when the perithecia were ejecting 
their spores, ees perithecia were taken and crushed be a blunt 
needle in a 
n thus treated, the glass slide with 
noculated was 
n fingers moistened with distilled water, so as t0 
give a ss 2 “dutians to the leaf, and the drop 
transferred to the moist surface of the leaf. Three or four leaves 
were inoculate: in each pot, the remainder of the leaves, about ten, 
ontrols. Direct 
y after inoculation the pot was covered 
ed with 4 
cp borin periment (Exper. no. 1) ascospores were sown 02 
sealing — s(t day pos pong to of oats, wheat, and — No infec- 
