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for Systematic Biology. 
I do not know who is the author of the saying, but systematic 
work has been described as “ the taking of snapshots at the pro- 
cession of life.” That is exactly my ideal, but I deny that our 
‘species’ are snapshots at any procession of Nature. Let us by 
all means snapshot the forms of life which come within our range 
and leave it to future generations to arrange the ‘ procession ’ as 
our labour shall slowly reconstruct it. But when we place one 
form called a ‘ type ’ at the head, and trail others anyhow after 
it as varieties, our “ snapshot of the procession ” becomes a ‘ fake ’ 
unpardonable in the domain of science. 
I can, however, understand a philosophical difficulty being 
here thrown in my way. It is this. We cannot possibly deal 
with all the finer shades of variation ; we have neither eyes to 
see them nor instruments to measure, nor means to test their 
value or to unravel the complexities of concomitant variations 
in the more specialized organisms. We shall still have to ‘ lump’ 
the forms together and our method will after all be the same as 
that which is now adopted. While this may be verbally true, 
for our most perfect method can only be an approximation, it is 
practically false. I am contending that the doctrine of evolution 
demands that we should take the varying forms assumed by living 
organisms as the units of our classification. It is useless to say, 
“ But there are shades and complexity of variation which our 
powers of observation are not exact enough to enable us to 
appreciate.” All we have to do is to describe and designate those 
forms whose differences we can now appreciate. We do not really 
know what powers of observation we may not acquire so soon as 
we deliberately adopt this as our method of work. We already 
distinguish forms which our forefathers ‘ lumped ’ together and 
our systematists are describing thousands of apparently new forms 
almost every year, although unfortunately they continue to group 
them blindly into genetic ‘species’ with their varieties, thereby 
making assumptions which are not only useless but even seriously 
impede progress. 
The different forms, then, which we can distinguish must be 
our units, and we want a formula which will enable us to desig- 
nate them. We need not be appalled at the idea of having to 
try to group the almost infinite number of different forms assumed 
by living matter into evolutionary series. For unless our collec- 
tions are large enough to reveal to us series, we have nothing to 
do but to record the forms and what little fragments of series we 
form, as the type of a new “ species ” is universally denounced as a useless multi- 
plication of “ species.” And yet if the “ species ” is to continue to be the unit of 
work I cannot see what else a really conscientious worker can do. By conscientious 
worker I mean one who will not guess, and lays no claim to having any special 
“ feeling ” for species. 
