THE FLORA OF NORTH AMERICA. 255 
ously be hopeless. I need not say that our dependence, for 
the actual elaboration, must largely be upon associates, upon 
the few who have the training and the vast patience, and the 
access to herbaria and libraries, requisite for this kind of 
work, but above all upon my associate in the herbarium at 
Cambridge, to whom, being present with us, I will not further 
allude. * 
Of course we rely, very much indeed, upon the continued 
cooperation of all the cultivators of botany in the country; 
and it is gratifying to know that their number is increasing, 
new ones not less zealous than the old, and better equipped, 
are taking the place of those that have passed away, and some 
of them extending their exploration over the remotest parts 
of the land, and into districts where there is most to be dis- 
covered. All can help on the work, and all are doing so, 
by communication of specimens and of observations. Those 
within the range of the published Manuals and Floras get 
on — or should get on — with only occasional help from us. 
They should send us notes and specimens to any amount; but 
they should not ask us to stop to examine and name their 
plants, except in special cases, which we are always ready 
enough to take up. Those who collect in regions as yet des- 
titute of such advantages may claim more aid, and we take 
great pains to render it: partly on our own account, that we 
may assort their contributions into their proper places, partly 
for the encouragement of such correspondents, who otherwise 
would not know what they have obtained, and who naturally 
like to know when they have made interesting discoveries. 
But the scattered and piecemeal study of plants is neither 
very satisfactory nor safe. And it involves great loss of time, 
besides interrupting that continuity and concentration of at- 
tention which the proper study of any group of plants de- 
mands. As respects the orders of plants which are yet to be 
elaborated for the Flora, and as to plants which require criti- 
cal study or minute examination, necessarily consuming much 
time, it is better to defer their complete determination until 
the groups to which they severally belong are regularly taken 
in hand. 
