302 
the more so as other changes had to be made in any case. I am 
alluding to the circumscription of the species Andropogon Nardus 
and A. Schoenanthus of Hackel’s monograph. They have become 
overloaded with subspecies and varieties just as the genus 
Andropogon has become overloaded with subgenera. Theoretically 
there is little or no objection to the subordination of those forms 
under a group of higher rank ; but it appears to me inexpedient 
to introduce those theoretical conclusions into what I may call 
our everyday nomenclature, which should be short, plain and 
direct. The species as I have defined them are with few 
. exceptions, geographically, morphologically, and as far as we can 
see at present, also physiologically tolerably well defined, and 
those which are in cultivation have proved remarkably constant. 
The complexity of the historical and argumentative part of the 
matter has obliged me to extend the volume of the paper so 
much that it is desirable to divide it into two parts. In the 
first part I attempt to givea circumstantial account of the botanical 
and economical history of the oil-grasses. The second is more 
of the nature of a résumé with the addition of such data as either 
result directly from the conclusions arrived at (e.g., most of the 
Synonyms) or have been thought worth including as a further 
help in the identification of the oil-grasses (¢.g., the enumeration 
of herbarium specimens and vernaculars). {[ have not thought it 
necessary to describe the species at length, as descriptions already 
exist, although in several cases the describers have treated some 
of the grasses merely as varieties. It has seemed to me, however, 
useful to add an expanded key to the species. This contains all 
that is essential for naming purposes; references to more extensive 
descriptions may be found under the heading ‘ Descriptions.’ | 
I—BOTANICAL AND ECONOMICAL HISTORY OF THE 
OIL-GRASSES. 
All the oil-yielding grasses of India belong to the tribe Andro- 
pogoneae, which is, on the whole, rich in more or less aromatic 
species. No attempt has been made to treat them comprehensively 
from that standpoint, and practically nothing is known of the nature 
and distribution of the oil-containing tissues and their functions. 
The oils themselves have been examined in a few instances and 
their chemical constitution and physical properties ascertained ; 
but even in those cases a renewed examination is desirable as the 
botanical identification of the material examined is not always 
above suspicion. 
The aromatic character of some of those grasses is so pronounced 
as to have attracted the attention of man at a very early period of 
his history. They found a place in the performance of religious 
rites, among domestic medicines, in the dispensaries of the 
medical practitioners, and in the department of spices and 
perfumes. The “Schoenanthus” of the Ancients, the “ Viranam ” 
of the Vedhas and the ‘“Sereh” of the Malays are illustrative | 
instances, and there is very little doubt that the much discussed 
kadAapoc dowpariudc Of the Greek writers was a plant of the same 
category although we have not so far succeeded in fixing the 
