1917] CURRENT LITERATURE 169 
ganic salt relations of plants, and relation of plants to climatic conditions. A 
quotation from the book expresses the point of view under which the work of 
the moiassaas ie is wing conducted. 
summarize e last age Paragraphs, our operations have been and are 
ae toward ad The point of view here employed 
may perhaps be envisaged if the reader will an the living plant in somewhat the 
same general way as he might any complex machine, such as a gasoline motor, for 
example. To understand its aera one must understand how and how much 
to be engineering science as applied to the living plant. It can progress, then, only 
through quantitative studies, through the comparison of efficiency graphs and curve- 
tracings made by recording instruments, through the mathematical interpretation of 
relations between conditions and process rates, etc., and it is with agg this sort of 
studies that our investigations have to do. 
It might be well if scientific d t g lly issued such statements 
of their aims —_ progress.—WM. CROCKER. 
NOTES FOR STUDENTS 
Rhizoctonia.—In a paper constituting a continuati Sf hie satin 
the genus Rhizoctonia, ErtKsson? adds. an account of two further forms, 
R. Medicaginis DC. and R. Asparagi Fuckel. The paper deals largely with 
historical and descriptive matter; the chief interest, ; 
questions relating to the taxonomy and id morphology of ‘th 
the Tut Do BP iadi-ncins 
Hance f the pha of the geminata Lo ue 
bs iting stage an calor fis < ic which he Had doxbs = 2 
