60 
Psyche 
[September 
strewn with irregular, short, villous processes’’ and carry 
much dirt so that “neither colour, texture, nor markings 
can be seen” (except N. targionii Mich.)* Thus Linne’s 
color and texture characters are not specific (except that 
they throw out N. targionii) , the color possibly being that 
of the extraneous matter coating the back and the scabrous- 
ness may also be due to this “stucco.” 
The only species of this restricted group recorded as 
found in Sweden by Tragardh is N. segnis. Michael (1888, 
p. 514) says that N. biverrucatus is not common, that N. bi- 
carinatus (p. 517) is common but arboreal, and that N. 
segnis (p. 521) is “chiefly found at the roots of mosses 
(on the ground) . . . not very common ... I have found 
it in Norway.” In connection with Michael’s figures it 
must be remembered that figure 1 (of N. segnis) is with 
nymph skin but that figure 6 (shaded portion) is what the 
podex looks like without the skin, thus being even more con- 
spicuously bidentate than N. biverrucatus ! Thus, until 
there is further evidence to the contrary I must regard 
N. segnis Michael a synonym of A. scaber L. 
Turning to Hermann’s N. segnis one is struck by the 
strongly bidentate podex, and the words “d’un cendre 
noiratre” which immediately recalls Linne’s “obscure 
cinereum.” Finally as Hermann’s figure shows the pseudo- 
stigmatic organ standing out beyond the body while in the 
adult they are much shorter, one must conclude that either 
he had before him some N. horridus as well as true N. segnis 
or that he figured a nymph of N. segnis. This latter seems 
still more certain from the fact that he omits the prominent 
rostral bristles. On the other hand, three claws are figured. 
As the figure is thus very evidently based on more than one 
individual and even more than one species, I would restrict 
only that part of the description and figure which refers to 
color (and pattern), bidentate podex and pseudostigmatic 
organs as type of Camisia Heyden. Acarus scaber Linne 
1758 thus becomes Camisia scaber (Linne). 
Oudemans’s only comment is, “This description betrays 
at once Camisia biverrucatus C. L. Koch.” This is an 
opinion, not evidence. 
Of the 18 other references given by Oudemans, 17 of 
them are of relists in compilations and translations, or later 
