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MESSRS. C. WARBURTON AND N. D. F. PEARCE ON | Dec. 12, 
Subfam. SERRARIINA. 
Gen. SerraArius Michael. 
SERRARIUS MICROCEPHALUS Nicolet. 
This interesting species, which Mr. Michael in his ‘ British 
Oribatide’ describes as occurring rarely at Epping Forest, the 
Land’s End, and Swanage, was found in abundance in the autumn 
of 1904 in the moss of an osier-bed at Grantchester, Cambridge, 
and several specimens of the nymph, hitherto unknown, were 
discovered. ‘This is a remarkable creature, entirely unlike the 
imago, and has the habit of carrying on its back the cast larval 
and nymphal notogastral skins (Plate XIX. fig. 3). As each of 
these skins bears round its edge eighteen conspicuous spines, 
proceeding from short apophyses, the. fully-grown nymph has a 
remarkably spiny appearance. The colour is pale yellow and the 
surface finely punctate. 
In 1879 Kramer (in the Archiv f. Nat., Jahrg. 45, Bd. i. p. 16) 
described a new species of mite which he named G'ustavia sol, 
which, so far as we have been able to ascertain, only Oudemans 
has suspected of belonging to the Oribatide. He states that it 
is probably the nymph of a Serrarius. A glance at Kramer’s 
figure at once makes it perfectly clear that he was dealing with a 
Serrarius nymph, and he even gives a drawing of the mandible, 
perfectly characteristic in shape, but lacking the serration, which 
is always difficult to see. He mentions no locality, and attributes 
to the animal a size much too large (1:2 mm.) for either of the 
known Huropean species of Serrariws. Possibly the length given is 
intended to include the legs. In any case, Gustavia sol Kramer 
can now be stated to be a nymph of Serrariws, as Oudemans 
suspected. 
Subfam. NovasPiIpIN2. 
Gen. Liacarus Michael. 
LIACARUS BICORNIS, sp. nov. (Plate XIX. fig. 4.) 
Adult. Length 600 p. Colour red-brown. Surface highly 
polished. Lamelle, large blades on edge, near together and 
sub-parallel, but slightly converging anteriorly. Very long free- 
projecting cusps, from the extremities of which proceed the long 
lamellar hairs. Translamella and interlamellar hairs wanting. 
Pseudostigmatic organs long, filiform, curved upwards and 
slightly outwards. 
Abdomen very globular, with rather prominent shoulders, and 
with a few longish hairs. 
The coxa of the 4th leg is almost as long as the femur, and is 
produced anteriorly in a pointed blade. 
Three specimens were found in moss from Austwick in May 
1904, and one from moss from the river-bank near Ely, in July 
1905. 
Nymph and larva unknown. 
