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scanty groupings of—family—subfamily—genus — subgenus and 
species. Darwin in his Origin of Species, says “ groups of species such 
as orders, suborders, families, subfamilies and genera, seem to be at 
least at present almost arbitrary. ’ The outcome of all the research 
with regard to the structure of our insects has already been to reveal that 
subdivision is necessary, but do not let us create genera upon genera 
when we ought to be grouping them under some more intelligible 
heading. The jump from some of the more recent so-called genera, 
is, on consideration, altogether unintelligible, and by no means a 
statement of the valuable facts already gleaned, which should be part 
of the definition of science itself. It need hardly be remarked that, if 
our genera are so ill-defined, our families must also be ill-defined and of 
a flexible nature. In our primary grouping, namely, that of common 
individuals to a species, we try and make our heading as narrowed as 
we can. We recognise that varieties are not entitled to be called 
species, and also that subvarieties are not entitled to be called varieties 
and we endeavour to keep them separated and thus defined, although 
all come under the broad head or family relationship of species. The 
aberration that occurs with the type is only just commencing to become 
individualised, while the variety which we call a race, which is separated 
in some particular spot, is much nearer becoming a species. We 
make these distinctions in the lowest subdivision, although we still 
require a vast number more names for the great number of various 
stages previous to an individual’s becoming a species. Let us look at 
some of our well known British species. We have perhaps not yet 
forgotten the Tephrosia tangle and the amount of discussion that it 
aroused, the question being whether we had a particular two species 
that were very similar or only one. The summary as set forth by 
Tutt was this: “We have (1) the differences in the eggs; (2) the 
differences in the general character and appearance of the imagines; 
(3) the difference in the shape of the wings ; (4) the independent life- 
histories of the two insects; (5) the constant difference in the times 
of appearance; (6) the fixed double-broodedness of one and the single 
of the other ; (7) the fact that the two insects breed true, and always 
produce their own kind.” But although there are all these 
differences, what are they when we compare another species of the 
same genus that has differences of twice the number of characteristics ? 
That third species must have passed through many more phases 
before it arrived at all these differences, and has probably taken a much 
longer period also to develop them. And my question comes to this— 
What is the value of a species, or rather what is the minimum diver¬ 
gence in time, structure, habit, or any other characteristic, taken 
severally or conjointly, that is to determine whether we have a species 
or not ? If we are to settle this by saying that it is a matter for 
individual opinion to decide whether the amount of divergence is 
sufficient, then we must see that as all our species have not been 
described by one individual, we must have a large number of very 
unequal species. Even if the one individual could have described all 
the species, as all these species have not become so on the same lines, 
it must have been almost impossible to weigh characteristic with 
characteristic, so that every species should have passed through an 
equal amount of specialisation. In regard to the former remarks, the 
multitude of describers with their varying ideas as to a species, has 
