(53) 
effects, likewise, may thus be observed, obliging the most skeptical to admit 
the agency of the parasites in causing the malady to which attention is given. 
Probably Prevost first discovered the fact, that the spores of fungi 
germinate. This was in the first decade of our century. Since then many 
eminent naturalists have given abundant testimony as to the true parasitism 
of species, and of their individuality as such. We may, without disparag- 
ment to others, mention the names of Leville (4), Tulasne (5), Berkeley (6), 
and M. Bary (7) as authorities, whose writings have conclusively 
established the fact that these parasites do cause the maladies attrib- 
uted to them. Iiobin (8) and Leidy (9; have published prominent treaties 
on the vegetable parasites upon living animals. 
Observers in this field are now much more numerous than ever before 
and, having the advantage of the former contributions, are gaining rapidly 
in the knowledge of kinds and of the injuries caused by these small but in 
no wise insignificant organisms. Preventives and cures naturally follow 
investigations of cause. They certainly cannot precede the latter except 
by accident • hence, if any one feels like asking “ What use ? ” let him 
possess himself in patience ; — in the coming time, man will assert his 
dominion here as well as elsewhere over the natural world. Something has 
already been done. The vine disease in Europe has been kept down by the 
use of sulphur, as are the rose and verbena mildews in green-houses. Some- 
times prevention is attained by removing promptly attacked parts, as in the 
case of the peach-rot, and, as further detailed below, sometimes by destroy- 
ing the spores of the fungus, as in the bunt of wheat. Cultivators now often 
unconsciously scatter the germs and ignorantly provide ways and means for 
their development. The march or migration of a parasite of this kind is 
sometimes as well marked as that of an injurious species of insect. 
Puccinia malvacearum , Mont., affecting cultivated hollyhocks, has been 
traced from South America through the United States To England and thence 
to the continent as certainly as the Colorado potato beetle has across our 
territory. Timely, intelligent action in such cases might avert great disas- 
ter. Had this fungus attacked the cotton plant, as it was feared it would, 
what estimate could be placed upon the loss ! What money- value is de- 
stroyed in our own state by rust (. Puccinia graminis , Pers .) on wheat, oats, etc.; 
what discouraging losses by the multitudinous blights upon our cultivated 
crops, many of which are known, and others supposed to be, caused by para- 
sitic fungi ! 
4. Annales des Sc. Naturelles, 1839, etc.; and “Mycologie,” and “Uredines,” 
in Diet. d’Hist. Nat., par D’Orbigny. 
5. Annales des Sc. Naturelles, 3 ser., tome VII, 1847 ; 4 ser., tome II, 1854. 
6. Introduction to Cryptogamic Botany, London, 1857, p. 261. Outlines of 
British Fungology, London, 1860, p. 68. 
7. Ueber der Brandpilze, 1853. Morphologie und Physiologie der Pilze, 1866, 
and many papers in Annales des Sciences Naturelles and elsewhere. 
8. Historie Naturelle des Vegetaux Parasites qui croissent sur Phomme et sur 
les animaux vivants, par Charles Robin, Paris, 1853. 
9. A Flora and Fauna Within Living Animals, by Joseph Leidy, Smithsonian 
Cont. to Knowl., Vol. 5, 1853. 
