568 ON BRITISH MITES OF THE FAMILY ORIBATIDE. [ Dec. 12, 
Claws monodactyle. Pseudostigmatic organs long and fili- 
form. 
Nymph and larva unknown. 
This fine species is closely allied to WV. targionti Berlese, but 
may be distinguished from it by the much longer, wavy, wn- 
pectinated hairs on the notogaster. The apophyses from which 
these hairs spring are very small, while in WV. targiont they are 
exceedingly conspicuous. 
A single example was sent by Mr. W. Evans, taken at Loch 
Gally, Fife, in May 1905. Another specimen was found by us in 
Sphagnum from Blairgowrie, Perthshire, in November 1905. 
This species, even more strongly than 1. targionit, recalls 
Hermannia bistriata, and in these three forms the two genera 
approach one another very closely. ; 
Norurus TecroruM Berlese. (Plate XX. fig. 4.) (Hypocthonius 
tectorwm Berlese, Acari Myriapoda et Scorpiones etc., fase. 78, 
no. 8, 1896.) 
This species, which we at first regarded as new to science and 
which may be easily recognised from the figure (Pl. XX. fig. 4), 
is no doubt identical with the Hypocthonius tectorum of Berlese. 
That arvachnologist has, we believe, been misled by an apparent 
segmentation artificially produced by slight pressure in mounting. 
We have examined many living specimens, and specimens mounted 
without pressure, and these present no trace of segmentation ; 
but we find that a transverse furrow (varying slightly in position 
and width) is readily produced in the soft integument when the 
cover-slip is allowed to press somewhat heavily upon it. The 
species must therefore be removed to the genus Nothrus, to 
which it undoubtably belongs. 
Not rare in moss from walls and house-roofs at Grantchester, 
Cambridge. 
NOTHRUS CRASSUS, Sp. nov. (Plate XX. fig. 5.) 
Length 500 ~. Colour light yellow-brown. Integument smooth 
and very imperfectly chitinised. Claws tridactyle. Pseudostigmata 
fairly large but not very projecting. Pseudostigmatic organs 
spindle-shaped, often directed backwards, and rather large. 
Genital and anal plates large and close together. 
An aquatic or amphibious species occurring in Sphagnwm in 
heath-pools near Bournemouth, in company with 1. glaber and 
N. monodactylus. 
Of the not very well-defined genus NMothrus the five species 
tectorum, turdus, glaber, monodactylus, and crassus form a compact 
group, agreeing in the rounded form of the abdomen and in their 
very slight degree of chitinisation. Tectorwm and tardus are 
terrestrial species, while the other three always occur in or near 
vater, and in glaber and monodactylus the pseudostigmatic organs 
are absent. 
