32 BOTANICAL GAZETTE [yuLy 
vigorous stalks, each with a single infection contracted earlier in the 
season, which now appears as an almost pure teleutospore formation 
directly on the green stalks. The value of these spores as reproduc- 
tive bodies is doubtful, as they will not germinate at any time during 
the summer. Apparently this is rather the form assumed by the 
fungus under unfavorable conditions, when infection could not take 
place, producing only the resting, teleuto stage. If such a stalk be 
placed in a moist chamber, there immediately breaks out at the 
outer edge of the infected area a circle of uredosori, with spores 
capable of immediate germination. The same occurs in nature 
later in the season as the dew becomes more abundant. Here again © 
uredo development, proving that the fungus not only requires mois- ~ 
ture for the germination of its spores and for infection, but has the 
same requirement for the production of spore forms capable of imme- 
diate germination. Experiments by the writer show that both the 
aecidiospores and uredospores of this fungus are comparatively 
short-lived, but that the teleutospores are capable of lying dormant 
for long periods and have a strong relation to the effect of frost in — 
their germination. This also shows the teleuto stage as not neces- — 
sarily a fall rust, but as occurring regularly under other conditions 
extremely unfavorable to the further development of the fungus. 
It is to be understood that these stages described are not indi- 
vidual cases, but the regular development of the asparagus rust in 
such a district as this. In September moisture becomes a little — 
more abundant, varying locally with the amount of irrigation and 
other conditions, ‘and now begins the regular uredo epidemic. Thi 
main beds in the open were affected. It is scarcely necessary to 
say that such places will be avoided by growers in the future. 
In the latter part of September the rust gradually works out into — 
the open fields. The trade wind is now subsiding, but blows fitfully 
for days at a time. The disease still seeks shelter from this drying 
influence and appears first on the east side of north and south rows 
