MR. G. BENTHAM ON GRAMINES. 25 
means pretend to assert it asa proved fact. If the suggestion be 
confirmed, we might be justified in designating as a neutral flower 
that in which the palea alone, or the palea and lodicules without 
stamens or pistil, are developed; but we must not include in the 
flower the bract or glume which subtends it. 
In all cases the palea, whatever its origin, is called upon in con- 
Junction with the subtending glume to perform more or less of the 
functions of the defieient or absent perianth, and thus acquires a 
certain fixity of character, and requires mention in all full generic 
characters. The lodicules, on the other hand, are generally rudi- 
mentary representatives of suppressed organs having Jost all func- 
tional powers, and their slight variations in form or consistency 
are generally not even of specific importance, and they only re- 
quire mention in generic characters in the few cases where they 
have retained a greater and more constant development. 
There is much of interest in the question of the geographical 
distribution of Grasses as compared with that of Orchidee, and in 
the consideration of the causes which have produced the differ- 
ences observed in the two Orders, amongst which perhaps the very 
different agencies through which cross-fertilization is effected may 
be most influential; these questions may have also more or less 
bearing on tribual and generie arrangement; and there are nume- 
rous observations which I should have been desirous of recording. 
This, however, would lead to speculations which it would not be 
safe to indulge in without a far more detailed and closer study of 
ascertained facts than I have time to carry out ; and I feel obliged 
to confine myself on the present occasion to tlie purely systematic 
consideration of real or supposed affinities and diversities. 
The division of the Order into tribes and subtribes is a matter 
of exceptional difficulty. Whatever tribes have been proposed, 
whatever characters have been assigned to them, there have 
always been more or less ambiguous forms uniting them and 
preventing the restricting them within absolutely definite limits. 
We are obliged in Gramine&, more perhaps than in any other 
Order, to rely upon combinations of characters, allowing for 
occasional exceptions in every one of our groups, preferring 
those which experience has shown to present the fewest aberra- 
tions. Following up these views, none of the general divisions 
of the Order hitherto proposed have proved to be more natural 
or more definite than Brown’s original primary one into two 
great groups or suborders—Panicacee, in which the tendency to 
