BOTANICAL GAZETTE. 383 
presence by their results. They have singular, and, to the stu- 
dents of other forms of life, unfamiliar physiological powers and 
properties ; they assume peculiar disguises, and pass through un- 
looked-for stages of development, of which the connecting links 
are hard to make out; they lie dormant now, and again 
wondrously quickened and enormously multiplied under cireum- 
stances not readily traced. But little by little, qualified observers 
have acquainted themselves with their existence as true species, 
veritable and distinct plants, and little by little have learned 
something of the mysteries of their life histories. Sometimes 
the advance in knowledge is gained by casual and lucky observa- 
tions; but mostly by painstaking, systematic research, aided by 
all the appliances of the equipped laboratory and the fruitful skill 
of trained powers of manipulation and acute perception. A step 
gained is not only so much secured, but renders more possible 
other or further advance. The more becomes known, the easier 
progress is made, since that already acquired points the way to- 
wards new achievements. The beginning has been made, though 
this can scarcely be said to have been true until within very re- 
cent times. The men are now living and working who have 
made known all the ascertained facts of physiological processes 
and results in these parasitic fungi. The germination of fungus 
Spores was not observed until within the present century. 
_ During the last part of the first half of this century learned 
discussions arose upon the specific distinctions between the para- 
Site and the host, and esteemed botanists held the view that what 
was taken for the former was but a diseased condition of the lat- 
y the degraded cell- 
f opinion, however, 
ssion of the infor- 
the tissues of the | lant, it began its growt 
latter and gained ‘trode a oa te forcible entrance. “pores 
are never taken up by absorption and carried by aqueous as 
rom part to part of the plant. The fungus passes revere 
sues very much as roots pass through the soil, somenine: sf 
Patently without in any degree successful opposition, a ~ : 
“aaa or quite baffled in the struggle by the mechamica’ ® 
Phy Siological resistance of the host plant. 
