62 FIFTH ANNUAL REPORT 



depletion of sap. The conditions of a soldier in an army — where 

 nian3' are camped and barracked together, and where it is difficult to 

 obtain hot water wherein to wash one's under-clothes — are favorable 

 to the increase of certain body parasites, and other more invisible 

 organisms, which produce disease. Yet, while in such a case the 

 conditions have assisted, it is very palpable that the organisms are the 

 direct cause of disease; and tliat if they can be warded off or re- 

 moved, the disease may be prevented, though the conditions remain. 

 Precisely in the same sense, I do not believe there would have been 

 the mortality among our vines had the lice been kept off or removed 

 from the roots. 



It is a noteworthy fact that, notwithstanding tlie loss of vines, the 

 general grape crop was large in 1S72, and prices were so low as 

 scarcely to be remunerative. It is very evident that the time is fast 

 approaching, if it has not already come, when the simple growing of 

 the Concord because it is hardy and bears neglect, will not pay; and 

 in the future, only tliose viticulturists — basing their operations on more 

 knowledge, more science — who can grow the finer qualitied varie- 

 ties, will find the business remunerative. One of the first requisites 

 of success with these latter is, to my mind, a full understanding and 

 management of the Phylloxera^ and I am not without hope that 

 those who do obtain this knowledge, and who put it into practice, 

 will yet be masters of the situation, and succeed with the Wilder, the 

 Goethe, the Catawba, the Walter, the lona and other varieties of ac- 

 knowledged excellence, but which are at present precarious. 



I am aware that it is difficult to bring home to the average vint- 

 ner any just sense of the importance of a microscopic atom, which is 

 naturally hidden from his eyes, and which it requires some effort and 

 training to see, and still greater effort to understand. There are few 

 so simple as to deny the injury caused by the Chinch-bug, the Colo- 

 rado Potato-beetle, and such other insects as, from their conspicuous 

 size, render their presence and their ravages too patent; but where 

 the enemy is so much more insidious, there will always be those who 

 will deny its existence, or who, when made to see it by the aid of 

 others, will prefer to look upon it as the effect rather than the cause 

 of disease, and to attribute the disease itself to other causes. It is so 

 much easier to deductively jump to hypothetical conclusions than to 

 patiently and laboriously work out the truth by induction, and the 

 proneness to attribute insect injuries to meteorological influences, 

 and especially to drouth, is exemplified in the past history of many 

 insect pests, and in that of the Hickory Bark-borer, given further on. 



KANGE OF TILE INSECT IN NORTH AMERICA. 



I have found the galls abundant on wild vines of the species 

 Rijparia as far west as Manhattan, Kansas, and that it extends as far 

 •south as Florida, we learn from a communication from L. H. Tallman, 



