274 Mr Bernard, On the Unit of Classification 
ally imposed upon our forefathers and still impose upon us, 
whereas it is the form in the abstract which they reproduce 
which alone concerns the evolutionist and it is a matter of 
absolute indifference to him, however interesting it may be to 
the biologist, whether any particular form has been reproduced 
only twice or millions of times. Evolutionary classification has to 
endeavour to arrange each particular form in its order of develop- 
ment above the forms from which it can be derived and below 
those to which it has itself given rise. 
And here in passing I should like to remark that I am only 
developing the teaching of my honoured friend and teacher Prof. 
Ernst Haeckel, who 30 years ago in his Biologie der Kalk 
Schwamme insisted that classification was worthless unless based 
upon profound morphological study. It is the neglect of this 
teaching which has made modern Systematic Zoology what Dr 
Dohrn calls it 1 , an Augean stable. 
Now some may maintain that they really mean the abstract 
form when they say the species, thereby maintaining that the 
two can be practically treated as one and the same thing. This, 
however, is only true in the few accidental cases of exceptionable 
stability combined with complete morphological isolation, so that 
the form features of any single individual actually represent those 
of the whole group. But we cannot allow these rare cases to 
supply us: with a rule of work for all the rest of the organic world. 
We know that no genetic group is absolutely stable and that, 
therefore, the form of no single individual can be arbitrarily 
selected as a type of the rest without covering up and hiding 
exactly what it is the aim of our classification eventually to 
reveal to us, viz. the variations in the form features and their 
evolutionary interrelationships. The present plan of grouping a 
number of individuals which appear only slightly to differ from 
one another round a type would be vicious enough even if our 
types were selected after a careful survey of all the known facts, — 
at least until the available facts are very much more numerous 
than they now are. But, instead of our types being even selected, 
they are purely arbitrary ; the specimen which is accidentally first 
described becomes a type. This type is given special prominence 
and other specimens are more or less indiscriminately and solely 
according to the subjective feelings — or better, the morphological 
insight — of the individual worker associated with it as mere 
varieties. In the case of the more stable groups and of those 
easier to examine, the mischief done is not so great as it is in 
the case of the less stable and more difficult groups. There, the 
resulting confusion can not be described; it has to be experienced 2 . 
1 In a private letter to Mr F. Jeffrey Bell. 
2 I need hardly remind the reader that the description of every apparently varying 
