24 MR. G. S. BRADY ON BRITISH FRESHWATER MITES. [Jan. 2, 
Hab. Madagascar. 
This interesting little Warbler was sent by Mr. A. Kingdon from 
Madagascar, having been procured by that gentleman during a holi- 
day excursion in the neighbourhood of Antananarivo. The form of 
this new genus is closely allied to Phlewis, of which P. layardi, of 
South Africa, is the type; but it differs in the form of the tail, which 
is composed of long loose feathers of lax texture with distinctly sepa- 
rated webs, very much as in Stipiturus of Australia. The typical 
specimen was presented to the Museum by Mr. Algernon Peckover, of 
Wisbech, to whom its discoverer Mr. Kingdon had forwarded it. 
4. Notes on British Freshwater Mites. By Grorce Strew- 
arpson Brapy, M.D., F.L.S., C.M.Z.S., Professor of 
Natural History in the College of Physical Science, 
Newcastle-on-Tyne. 
[Received December 7, 1876.] 
(Plates III. and IV.) 
Though Acari occur pretty abundantly at various depths in the 
sea, extending, indeed, from the littoral zone to a depth of several 
fathoms, I am not aware that any species have been recorded as 
living in fresh water ; and it is unfortunate that, in the case of those 
which form the subject of the present paper, I am not able to say 
with absolute certainty that they really ved in the water whence 
they were taken. It is just possible, though not (as I think) at all 
likely, that some of them may be terrestrial species which have been 
washed accidentally into the lakes or ponds in which I found them. 
Against this view, however, the perfect preservation of the specimens, 
and the fact of their belonging to unknown species, must be allowed. 
considerable weight. I hope before long to be able to investigate 
the matter more closely, and to satisfy myself as to the real habitat 
of these little creatures. 
As regards Trombidium fuscum, at any rate, there can be no rea- 
sonable doubt: it has been found in so many places and in such 
abundance as to leave no misgiving as to its aquatic habitat. With 
this fact placed beyond doubt, and remembering that a closely allied 
family, the Hydrachna, occurs in great profusion in fresh water, 
there need scarcely be much hesitation in accepting as truly aquatic 
the species which I here venture to describe as new. 
The literature of the Acarina is much scattered; and I have had 
no opportunity of reference to some important papers by Nicolet, 
Claparéde, &c. The generic definitions given by Dugés, on which 
I chiefly depend, seem to require revision and amplification. At 
present it is not an easy matter to refer a new species to its proper 
genus; and it is quite possible that some of those now under consi- 
deration may eventually be found to belong to genera other than 
those to which I have assigned them. 
