nature of the group which the species found in certain localities or certain similar rocks may afford, and the circumstances under which the organic beings in question have lived, died, and been preserved for future investigation.—Ansted's Elementary Course of Geology.
Leiodon at Norwich.—Mr. T. G. Bayfield has recently called the attention of geologists to certain fossils discovered in the chalk at Norwich. The pit which yielded them is called the Lollard's Pit, whence a great quantity of chalk is annually removed. In 1858 a few vertebræ of Leiodon anceps were discovered, and identified by a tooth which was in their immediate proximity. In October, 1864, a number of bones of the same skeleton were found, including six vertebræ, a hundred fragments of other bones, and two of the large culture two-edged teeth, with two of the smaller kind from the inner part of the mouth.
Devilline.—A new mineral found in Cornwall with laugite, from which it differs in its lighter colour, its lamellar structure, and its silky lustre. From its composition it appears to be a hydrated subsulphate of copper, containing about 8 per cent. of lime, and nearly 3 per cent. of protoxide of iron.
The Ilford Mammoth.—A remarkably fine fossil head of Elephas primigenius has been found in the Pleistocene sands and clay at Ilford. The upper molars remain in place, and both tusks have also been preserved, one still in the socket, but seemingly having been twisted round by the weight of the head, when the fleshy tissue of its attachment had decomposed, and before the skeleton was finally embedded in the soil. The tusks are of spiral curvature, and measure along their medial line above 10 feet 6 inches in length. No such perfect skull of the true Mammoth has ever been found in England, nor anything comparable with this important example, so far as we are aware, except it may be the fine fossil elephant in the Chichester Museum, a specimen of which we have hard, but have not seen. The present specimen in scientific value can only be classed with the famous one at St. Petersburg, and we are glad to add that it has, by the promptitude of Mr. Waterhouse and the trustees, been obtained for our National Collection; while to Mr. Davis, who was despatched by the Museum authorities to extricate this gigantic fragile mass from the rough loose earth of the quarry, too much praise cannot be given for the successful manner in which has has accomplished that difficult task.—Athenæum.
Hymenophyllum Tunbridgense and Wilsoni.—Great difficulty is sometimes experienced getting these tender ferns to grow in closed cases. A piece of muslin placed at the top of the case to arrest some of the light has great influence.
MICROSCOPY.
The Invisible World revealed.—To an intelligent person, who has previously obtained a general idea of the nature of the objects about to be submitted to his inspection, a group of living animalcules, seen under a powerful microscope for the first time, presents a scene of extraordinary interest, and never fails to call fort an expression of amazement and admiration. This statement admits of an easy illustration; for example, from some water containing aquatic plants, collected from a pond on Clapham Common, I select a small twig, to which are attached a few delicate flakes, apparently of slime or jelly; some minute fibres, standing erect here and there on the twig, are also dimly visible to the naked eye. This twig with a drop or two of the water, we will put between two thin plates of glass, and place under the field of view of a microscope, having lenses that magnify the image of an object 200 times in linear dimensions. Upon looking through the instrument we find the fluid swarming with animals of various shapes and magnitudes. Some are darting through the water with great rapidity, while others are pursuing and devouring creatures more infinitesimal than themselves. Many are attached to the twig by long delicate threads (Vorticellæ); several have their bodies inclosed in a transparent tube, from one end of which the animal partly protrudes and then recedes (Flosculariæ); while numbers are covered by an elegant shell or case (Brachionus). The minutest kinds (Monads), many of which are so small that millions might be contained in a single drop of water, appear like animated globules, free, single, and of various colours, sporting about in every direction. Numerous species resemble pearly or opaline enps or vases, fringed round the margin with delicate fibres that are in constant oscillation (Vorticellæ). Some of these are attached by spiral tendrils; others are united by a slender stem to one common trunk, appearing like a bunch of hare-bells (Carchesium). Others are of a globular form, and grouped together in a definite pattern on a tabular or spherical membraneous case, for a certain period of their existence, and ultimately become detached and locomotive (Gonium and Volvox); while many are permanently clustered together, and die if separated from the parent mass. No organs of progressive motion, similar to those of beasts, birds, or fishes, are observable in these beings; yet they traverse the water with rapidity without the aid of limbs or fins; and, though many species are destitute of eyes, yet all possess an accurate perception of the presence of other bodies, and pursue and capture their prey with unerring purpose.—Dr. Mantell's Thoughts on Animalcules.
The Microscope Indoors.—For amusement and instruction with the microscope, we need scarcely