962 Ox the Microscopic and General Characters of [December, 
says: “ Those who believe in the propagation of the disease by the 
agency of insects, maintain that the disease is never manifested up- 
on healthy stock until after the young tree casts its first blossoms, 
and experiments for the purpose of testing their theory will be 
made by enveloping the young tree with netting, in such a man- 
ner as to exclude all insects during the period of bloom.” How- 
ever, the disease does appear very often on trees that have not 
blossomed ! 
On page 250 0f the same volume, referring to the abnormal 
branching, it says: 
“ This growth ts the only means of detecting the disease in young 
trees or those not bearing.” (The italics are mine. 
In the Pomological Report for 1873, under this head, the first 
and second methods of dissemination given, are as follows: 
1. “ By the intermingling of healthy roots with those of dis- 
eased trees, : 
2. “‘ By planting a healthy tree in a hole whence a diseased 
tree has been removed.” 
As I have stated before, all the roots that were examined by 
me, presented no abnormal appearance except the looseness of 
the cells; in no case were any filaments of a fungus found in the 
tissues, nor any spores, nor any indications that a fungus had ever 
been present. Those that claim that the disease is caused = 
root fungus, have never, to my knowledge, found any pres : 
fungi that is peculiar to the peach root, which is not found in many 
other roots as well. In my examinations I have found Mie 
growing upon the outside of the larger roots, but in every case 
have turned immediately to the oak root and found the nee 
condition of things there, and the oak did not have the yellows, °, 
and as far as could be seen, no disease of any sort. Not yeh , 
found any signs of a fungoid growth in or on the root that is no 
found on the roots of most any tree, I do not believe t 
disease can be transmitted from one tree to another by th oe 
means given above. se 
As to the second, if the fungus that causes the disease has _ - 
time to mature and give off its spores, it is probable that sm . S 
_ of them would fall upon the ground round about he : 
_ tree, and thus, if the tree is removed and another put in its geen 
_ the spores may, by some means, get upon the bark of ath ae 
__ tree and there, germinating, push their filaments into the tssue 
hat this 
e first 
