ecies do not, any more than in the higher groups,
vanish with increasing materials and more accurate research.

Another striking example of the same kind is seen in the genera Rubus
and Rosa, adduced by Mr. Darwin himself; for though the amplest
materials exist for a knowledge of these groups, and the most careful
research has been bestowed upon them, yet the various species have not
thereby been accurately limited and defined so as to satisfy the
majority of botanists. In Mr. Baker's revision of the British Roses,
just published by the Linnaean Society, the author includes under the
single species Rosa canina, no less than twenty-eight named _varieties_,
distinguished by more or less constant characters and often confined to
special localities; and to these are referred about seventy of the
_species_ of Continental and British botanists.

Dr. Hooker seems to have found the same thing in his study of the Arctic
flora. For though he has had much of the accumulated materials of his
predecessors to work upon, he continually expresses himself as unable to
do more than group the numerous and apparently fluctuating forms into
more or less imperfectly defined species. In his paper on the
"Distribution of Arctic Plants," (Trans. Linn. Soc. xxiii., p. 310) Dr.
Hooker says:--"The most able and experienced descriptive botanists vary
in their estimate of the value of the 'specific term' to a much greater
extent than is generally supposed." ... "I think I may safely affirm
that the 'specific term' has three different standard values, all
current in descriptive botany, but each more or less confined to one
class of observers." ... "This is no question of what is right or wrong
as to the real value of the specific term; I believe each is right
according to the standard he assumes as the specific."

Lastly, I will adduce Mr. Bates's researches on the Amazons. During
eleven years he accumulated vast materials, and carefully studied the
variation and distribution of insects. Yet he has shown that many
species of Lepidoptera, which before offered no special difficulties,
are in reality most intricately combined in a tangled web of affinities,
leading by such gradual steps from the slightest and least stable
variations to fixed races and well-marked species, that it is very often
impossible to draw those sharp dividing-lines which it is supposed that
a careful study and full materials will always enable us to do.

These few examples sho