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Show 416 MR. A. D. MICHAEL O N [June 3, Europe. There are only 102 known British species of Ori-batidae, and it is perhaps rather remarkable that I should have found a quarter of them in a two-months' tour in Algeria. Of the new species probably the most remarkable is the curious new Cceculus before referred to ; not only because there was only one species of this very exceptional genus known previously, but also on account of its size and the singular arrangement of the hairs on the cephalothorax. There are, however, other creatures of considerable interest. One of these I propose calling Notaspns bur-rowsii; it is rather a handsome Acarid, but is quite typical of the genus, and is just such a species as one might expect to find in England : it has not, however, been captured anywhere in Europe so far as I know. What really makes it noticeable is the example it affords of the very wide distribution of these minute creatures, a fact which I have called attention to more than once. The species is, I believe, unrecorded, but just before I left for Algeria the Rev. C. R. N. Burrows sent m e a small collection of Oribatidee which he had lately formed in the neighbourhood of Lake Winnipeg in Canada. He remarked that the species seemed mostly identical with the British, which proved to be the case, but amongst them were a few unrecorded, the most conspicuous of which was the present species, which I at once recognized when I found it in Algeria, where it is not uncommon. I cannot detect any difference between the African and the Canadian specimens. Another very curious creature is that which I propose to call Damceus phalangioides. The various species of this genus have mostly long and slender legs, as compared with other Oribatidae, but in the present species this character is exaggerated to such an extent that it would hardly have been supposed that they could remain unbroken when the extreme brittleness of the chitin in this family of Acarina is remembered. Another new species of the same genus is exceptional, viz., that called D.patel-loicles. Almost all the members of the genus have a more or less globular abdomen, or else one which is discoidal, the latter being considered a separate genus by some Acarologists. In the present species the abdomen is pyramidal, a form which I do not think is found again in any known member of the family; in order to appreciate this shape the creature must be seen sideways, I have therefore drawn it in that position. An Acarid which is not, I think, new, is nevertheless interesting on account of a difference between the Algerian specimens and those hitherto recorded in Europe. With the single exception about to be mentioned, all known Oribatidse have either nionodactyle or tridactyle claws. Among the tridactyle claws some are homodaetyle, i. e. have the three claws similar; others are heterodactyle, i. e. have the central claw different from the lateral pair; usually the central is much the stronger, the lateral claws being thin and weak. It was formerly thought that Oribatidse could be classified chiefly by these differences of the claws, but wider knowledge has shown that any such classification would be extremely artificial. There is an English and European species called Nothrus sylvestris, which is |