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Show 1890.] ACARINA FHOM ALGERIA. 415 hood, an excursion was made to the high mountain-district of the Djurdjura at Fort National. On leaving Algiers I continued westward to Blidah, and again reached the coast at Cherchel, then to the hill-country of H a m m a m R'hira (well known as a collecting-place for Coleoptera) and Milianah; thence inland to the cedar-forest of Teniet-el-Ahd, some parts of which are about 5000 feet above the level of the sea, then to Tlemcen at the extreme west (or Moroccan) border of Algeria, and finally to the port of Oran. The first thing that struck me was the entire absence, in this order of creatures, of that teeming life which one might have hoped to find in a southern country ; the species were, I think, fewer in number, and certainly there were fewer specimens of each species than I should usually find under equally favourable circumstances during a search of similar length in England; nor do the species which are not British appear to be larger or more robust than those found in England. Very little is known of the Acarina of tropical or southern extra-European lands : the parasitic Ixodidae get sent home to Museums, and they attain a comparatively large size; but with this exception I have found that such species as I have been able to obtain from the warmer parts of the world have not, on the average, been larger or more conspicuous than the British or Mid- European. Another thing which struck m e was the absence of any types which are, I will not say African, because we are entirely ignorant what, if any, the African types are, but of any types sufficiently different from the European to necessitate a new genus. Of course we should expect the bulk of the species to be identical with those inhabiting Southern Europe; and so they are, but we might have anticipated that a few would have been found departing more widely from their European relatives. In spite of this there are several new species, and some of these are curious and interesting. The collection, with one single exception, consists wholly of Oribatidae; the exception is a remarkable creature, and forms a second species of the singular genus Cceculus, which will not fit into any of the existing families, and has hitherto consisted of one species only. In addition to these I found one or two Gamasidae and Trombididae, but only scattered specimens of species which are extremely abundant in England and most other, parts of Europe. I have not thought it worth while to record these. I think the season must have been favourable for searching all parts except the very elevated districts such as Fort National and Teniet-el-Ahd; it was rather early for these. Somewhat to my surprise there was a remarkable absence of all Acarine life in the truly southern vegetation, such as palms, bananas, prickly pears, &c, both when growing and in decay. I had not any opportunity of collecting the parasitic species of Acari nor the "Water-Mites. The collection consists of forty-four species belonging to fifteen genera. Of these species eight are new to science, twenty-five are found in Britain, and the remainder are natives of Southern |