REVIEWS AND ORITICISMS. 25 
tion experiments have thus far failed to prove that these 
micro-organisms are to bear the odium of having incited the 
disease. This line of investigation is, however, not yet closed, 
and more information in regard to it may be expected in the 
future. 
The general character and effects of the malady are well 
outlined and comparisons are drawn between it and diseases 
of the vine which are better understood. Of the vine para- 
sites already known, the fungus Uncinula spiralis is the 
* only one present in Southern California in sufficient abun- 
dance to place it under suspicion, but if this fungus is the 
exciting cause, its results are quite different in this region 
from what they are known to be elsewhere. The relation of 
Uncinula to the affection is to be further investigated. 
Many experiments have been made in the direction of pre- 
ventive treatment, but blindly, inasmuch as the nature of the 
disease is not understood. Mr. Pierce suggests that for the 
present the vines be treated with the Bordeaux mixture and 
be kept as free as possible from Uncinula by the application 
of sulphur. 
Although one, after reading the report, may experience a 
shade of disappointment that the cause of the trouble is still 
unlocated, yet it is evident that if the disease is ever to be 
understood and successfully combated, it is likely to be by 
the means of just such methodical and painstaking investi- 
gation as those conducted by Mr. Pierce. The report 
furnishes a good illustration of the methods of research 
employed in the recently developed science of vegetable 
pathology—M. A. Hows. 
Flora of West Virginia. By CHARLES F. Mitispaven, M. D. 
Being Bulletin No. 24 of the West Virginia Agricult- 
ural Experiment Station, Morgantown, W. Va., 1892. 
This is the most important of the recent local Catalogues 
that have appeared in America; for, while there are no 
diagnoses of genera, or of species except in the cases of a 
small number of new ones, valuable information is given 
