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Psyche 
[September 
tirely distinct from A. geniculatus as the color and shape of 
femora are different and because A. corticalis was described 
in 1778 when DeGeer was well aware of A. geniculatus. 
Oudemans, on the other hand (part II, p. 779) claims the 
two to be identical and thinks it “strange” that DeGeer 
should have used a new name and made no mention of 
A. geniculatus. Since the two are described as different, 
DeGeer was right in giving his later find a new name. Thus 
we are limited to Linne only for the description of A. geni- 
culatus. 
Trombidium corticale Rathke 1799 is a Norwegian species 
which will also have to await reidentification. This should be 
possible by a thorough study of all Oribatids which may be 
found in the same type of environment in that part of 
Norway. 
Acarus coleoptratus Shaw 1800. A comparison of his 
figure with that of Hooke 1665, will show considerable dif- 
ference. Further, Shaw says his species is “somewhat 
glossy,” while Hooke says “indented or pitted with an 
abundance of small pits, all covered over with little white 
bristles.” Shaw distinctly shows two nails per foot, Hooke 
but one (yet Hooke saw punctures). The reidentification 
of Shaw’s species will not affect nomenclature. 
Thus of the six species placed by Oudemans under one 
term, we find that on careful examination none are synony- 
mous. 
In a similar way one may go through the remainder of his 
compendium. His task was stupendous . and would need 
years of detailed work in various countries before it could 
be presented as a final piece of work. 
One thing Oudemans has done for which Acarologists 
should be grateful and that is he has brought together all 
early references on the group and with this as a broad work- 
ing basis we can each contribute our share towards clearing 
up certain species. 
A careful perusal of Oudemans’s comments on the various 
species reveals a well marked tendency on his part to state 
that the description or figures are incorrect if they do not 
fit the species which Oudemans has decided they should 
represent. This type of historical criticism carried on 
without a first hand knowledge of the local fauna con- 
