68 Dr Lauder Lindsay on the Flora of Iceland. 
which I have already in part mentioned incidentally. Such, 
for instance, as these :—It is a work specially devoted to the 
subject of which it treats; the author was an accomplished 
botanist and a native Icelander, resident in Iceland; the pre- 
sumption that such an author should have been better 
qualified to describe correctly the Flora of his own country 
than strangers merely visiting it, mostly for very short. 
periods; the probability that he was himself acquainted with 
the vegetation of the greater part of the island, and not 
only with a small section thereof; and also that he duly 
availed himself of the results of the inquiries and collections 
of all previous botanists. But since the date of publication 
of this work (1830), every botanist knows that great progress, 
or, if not in all cases great progress, at least great change, has 
taken place in the nomenclature and classification of plants. 
For example, the introduction and use of the microscope has 
almost revolutionised cryptogamic botany, particularly our 
knowledge of fungi and lichens. Many genera and species 
have been abolished as mere varieties, forms, or states of other 
species, while some of the old species have been subdivided 
into as many as four or five different genera! Under such 
circumstances, to determine the precise plant intended to be 
indicated by a particular name in some of the existing Ice- 
landic floras, is frequently absolutely impossible, and the 
endeavour to do so frivolous in the extreme. 
By others, however, the list of Vahl, and the chapters on 
Icelandic botany by Robert, may be regarded as at once the 
most recent and accurate Flora of Iceland. As I have already 
mentioned, M. Robert appears to have made a more syste- 
matic and complete exploration of Iceland than any previous 
or subsequent botanist, if we except Dr Hjaltalin; and I 
only presume that the latter was familiar with the greater part 
of his native island (there being still portions of it that never 
have been, and that perhaps never will be, thoroughly or at all 
explored!) Yet, so far from having added to former lists, Ro- 
bert does not seem to have collected all the plants enumerated 
by Vahl. It may hence be inferred, as I fear it has by some 
botanists been inferred, that no species new to Iceland, if not 
to science, remained to be discovered. Such a conclusion, 
