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Notes on the TJropodinae. By A. D. Michael. 
Berlese’s description of the adult makes it rather doubtful whether it 
should he so included ; hut as he is the only person who has seen the 
adult and he classifies it amongst the TJropodinae, I treat it as being 
so, relying upon his opinion. 
Celaeno. — This generic name, which is adopted by Berlese and 
Canestrini, cannot be maintained, because before Koch used it for a 
genus of Acari in 1835 it had been used by Leach for a genus of 
Mammalia in 1822; and Gelaena was used by Stephens for a genus 
of Lepidoptera in 1829. Even if the name had not been pre- 
occupied it could not, in my opinion, have been properly used for the 
present purpose, because, as already pointed out by Kramer, Koch’s 
Celaeno was a genus of Oribatidae , and the characters of that family, 
which is widely separated from the Gamasidae, must he included in it. 
Koch only put aegrota into the genus because he mistook it for one 
of the Oribatidae, to which family all the other species belong. Koch 
himself in the e Uebersicht ’ (Heft 3, p. 108), points out the absence 
of some of the principal characters of the Oribatidae, and says that 
aegrota cannot remain in the genus Celaeno , and is only put there 
because he did not know where else to put it. It is true that probably 
all these species are immature forms, and therefore it might he 
argued that the genus had failed and that a subsequent writer had a 
right to use the name for something else ; hut surely no one had a 
right to use it for the very creature which Koch had introduced in 
error, and refer the genus to Koch ; so that Koch’s definition of it, 
including all the Oribatid characters, would be supposed to mark out 
a group of creatures to all of which they were utterly inapplicable. 
As the generic names Trachynotus and Celaeno have failed I have 
called the genus “ Trachytes,” as being, I believe, the nearest unused 
name to Kramer’s. 
Polyaspis. — This is a genus on the very borderland of the Uro- 
podinae. There is not any recorded species which is known to have 
been found in Britain. I possess a species, but it is unrecorded; 
there is not any room on the plates accompanying the present paper 
for its illustration, and therefore I do not describe it. 
TJropodella. — There is not any known European species of this 
genus, nor have I ever seen a specimen. I have doubts whether it is 
properly included in the Uropodinae; 1 only do so because Berlese, 
who has seen the only known specimens, has done so. 
The following table will express my ideas. I have kept as closely 
to Berlese’s table as I could. 
Uropodin.®. 
Gamasidae with the genital aperture of the male within the sternal 
plate ; the camerostoma (camerostrum), or opening for the oral tube, 
ventral ; the dorsum projecting beyond it, and the first pair of legs 
