VOL. XII. NO.6.-BOTANICAL GAZETTE,—JUNE, 1887. 
The occurrence and function of certain nitrogenous bodies in 
plants. 
W. E. STONE. 
ence, destruction, transformation and functions are all sub- 
jects of discussion at present, as they have been for many 
years. Something of the difficulty met with in the study of 
element, and the difficulty of recognizing and isolating its 
various compounds as such. Micro-chemical methods fail 
for this purpose except in one or two cases, and, while purely 
chemical processes have accomplished a great deal, the dis- 
coveries announced from time to time, and the still existing 
gaps in theories, show that all the data are not yet at hand. 
A very practical and tangible illustration of this state of our 
knowledge occurs in the estimation and valuation of vegeta- 
ble nitrogen as a food element. For lack of a better general 
knowledge and methods the total nitrogen present is regarde 
as existing in the form of albumin, or in a few cases is class- 
ified as albuminoid and non-albuminoid, although it is well 
known that it may be present in a variety of forms of very 
different value and structure. If these different nitrogenous 
bodies have different values to the animal system, it is quite 
certain that they represent different physiological offices and 
uses In the living vegetable organism. 
During the past decade certain German investigators 
have done much toward determining (1) what these nitrog- 
€nous bodies are, and (2) what aa functions may be. 
The results of their work, scattered through various chemical 
and botanical journals, are not generally available to Amer- 
ican botanists, nor have they, so far as I know, been con- 
nectedly presented to them. For these reasons, no less than 
because it isa very important physiological subject, a general 
resumé has seemed desirable. : 
For the sake of convenience the vegetable nitrogenous 
bodies may be classified under two heads: those which play 
