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it. These scales are usually mounted "dry;" but Hogg recommends the use of Canada Balsam as rendering their structure more definite when illuminated with Wenham's parabolic reflector.—Davies on Preparing and Mounting Microscopic Objects.

.—Successful observation with very high powers is mainly dependent upon illumination. Indeed, by ordinary means it is not possible to obtain a light sufficiently intense to illustrate and object magnified 3,000 diameters. I have tried with greater or less success many different plans, and have used prisms, concave mirrors, and various kinds of condensers. I have, however, arrived at the conclusion that the most satisfactory results by far are obtained by the use of Kelner's eye-piece as a condenser, as suggested by my friend Mr. Brooke. By this means I can obtain a light sufficient for a magnifying power of 10,000 linear. I have tried the lime light, but have not found that it possesses any advantages over the belmontine or paraffin lamp, while the glare from it is much greater.—Dr. Beale's "How to work with the Microscope."

.—A gentleman having forwarded a packet of small stones covered with very minute white objects and acari, to Mr. Westwood, received the following reply:—"The minute white objects on the stones, are the eggs of the mite Trombidium (Tetranychus) lapidum, first figured by Hammer in Hermann's Mémoire Apterologique (pl. 7, fig. 7-8), with the eggs which were discovered in similar situations. Hammer's correspondent found with the eggs which were discovered in similar situations. Hammer's correspondent found with the eggs minute red-coloured six-legged mites which had been hatched from the eggs, and which ran very quickly. Accompanying these mites (with six legs) were always found others, two or three times larger, of a brown colour, and with eight legs, but these latter wanted the long setæ at the end of the four anterior legs of the small individuals. Hammer thought these constituted two distinct species, and that they were not varieties, different in stage or sex, because no metamorphoses had been noticed in these insects, and no individuals intermediate in size had been observed. He also inclined to regard the so-called eggs in consequence of their comparatively large size to that of the insects, as a kind of crysalid enclosing the mite in a sort of nymph state. From what has since been observed of the changes of these mites, however, there can be no doubt that the large specimens are full-grown individuals which had previously borne the appearance of the smaller ones. All this is the more necessary to be explained, because, in his note, Mr. Weatherhead states that the eight-legged mites were produced from the eggs. This, I believe, must be a mistake. Unfortunately I cannot make out the number of legs, the specimens in the small phial having been so battered by the particles of stone, that some of the legs may have been, as some certainly have been, detached in the journey from shaking about. I suppose also that this species is six-legged in the larval state. The eggs are beautiful microscopic objects."—Entomologist's Monthly Magazine.

, Dec. 5.—Mr. J. Weir exhibited some microscopic preparations of the spiral tongues of butterflies, for the purpose of showing the variation in the striation of the tongue in different species, and in the papillæ which exist at the end of the tongue.—Mr. Bond exhibited a coloured drawing of the larvæ of Acronycta strigosa, and a photograph of a remarkable negro variety of Abraxas grossulariata.—Mr. F. Smith exhibited a particoloured wasp's-nest, constructed by two species of wasp, the Vespa Germanica and V. vulgaris.—Mr. W. F. Evans sent for exhibition a box full of fragments of a Lamellicorn beetle, which had been picked out of some New Zealand wool: the insects proved to be Pyronota festiva, and it was conceived that, in the course of their flight, they had come in contact with the sheep and became entangled in the fleeces so as to prevent their escape,—The President exhibited some globular spiders' nests from South Australia, which were remarkable for their resemblance to the fruit of Leptospermum, the tea-plant of Australia, whilst the spiders themselves were described as looking like the excrement of a bird.—Mr. S. Stevens exhibited several pairs of Cheirolasia Burkei, one of the rare Goliath beetles of tropical Africa; he also read a letter from M. Du Chaillu, dated Fernand-Vaz River, Aug. 20, 1864, in which the writer announced the despatch to England of a large collection of insects.

, Dec. 6.—Mr. S. Laing exhibited an interesting collection, and read a Paper on "The Pre-Historic remains of Caithness." Mr. C. C. Blake also read a paper by Mr. Roberts on the discovery of a large Kistraem in the Muckle Hoeg, in the island of North Shetland, with notes upon the human remains discovered therein. An animated discussion on these Papers followed, in which Professor Owen and others took part.

, Dec. 12.—A Paper by Mr. J. Cameron, of Singapore, containing "A Description of the Islands of Kalatoa and Puloweh, north of Flores, in the Malay Archipelago." The former of these islands was said to be uninhabited, the latter to contain a population of 5,000, whose daily life was a repetition of the various stages of intoxication, and that every evening ended in a drunken brawl. Dr. Hector next read a paper on "An Expedition to the West Coast of Otago, New Zealand, and the Discovery of a practicable Route over the Mountains to the Goldfields and the East Coast." Mr. Albert Walker also gave an account of a hazardous journey which he performed, in company with two other young men, along the West Coast of the Middle Island, New Zealand.