30 



in the whole structure of a potato plant, the other process 

 ses of the fungus must be present also in an even more 

 diffused form, and I fail to see why it is unreasonable to 

 presume that the same is the case with Hemileia. I shall 

 attach Mr. Worthington Smith's remarkably lucid report to 

 these "Jottings" as well as an article from the "Gardeners 

 Chronicle" and hope I may be forgiven for the liberty I 

 have taken. 



lam aware that Mr. Smith does not say anything 

 about the disease entering by the root and that I may be 

 told that the fungus having attacked the leaves gradually 

 developed and extended to the tuber. My reply must be 

 that if leaf, haulm and tuber are liable to attack, and if the 

 resting spore remains in decayed portions of such in the 

 soil, that when a new crop is planted in the same field that 

 the roots as well as the other portions of such a plant would 

 be liable to attack also, and that if the pores of the leaf are 

 large enough to allow the entry of spores, that there is 

 every probability of ? the roots taking them up with even 

 greater facility. If the juices of a Coffee leaf are congenial 

 to the life> energy and requirements of the Hemileia, why 

 should we not think that the fungus probably extends its 

 operations beyond the leaf into the more juicy structures 

 in the body of the tree. Mr. Smith says pointedly that 

 even in the leaves it is extremely difficult to see such spores 

 even with a microscope and that to get them out is no easy 

 matter as they closely resemble the leaf-cells which are much 

 of the same color, and are almost as hard as wood. In Sir 

 Joseph Hooker's report printed in the Planter's Gazette of 

 July 31 1877, he remarks " Mr. Berkeley's examination of 

 " the Hemileia was made from dried coffee leaves transmit- 

 fc ted to this country. A first essential is a more adequate 

 " study of the fungus than such specimens could afford, 

 " especially in all details of its life histcry from gerraina- 



