yellowish in colour; the absence of epithelial elements is easily explained by the state of the animal. The structure of the organ recalling, in all its principal features, the constitution of the liver of the Crustacea and Mollusca; its affinities resembling those which it affects in certain of them (Squilla, &c.), oblige us to regard it as a new form in the worms, and show that if the majority of these animals deviate in this respect from the other Invertebrata, there are some which deserve to be classed with them and possess like them a true hepatic gland.* The Sting of the Honey Bee.-The new 'American Quarterly Microscopical Journal' commences with an article by Mr. J. D. Hyatt, of 11 pages (with 2 plates), on this object, which the author describes as one which " our naturalists have either imperfectly understood or else the records of their knowledge are so concealed in voluminous reports of scientific societies as to be practically inaccessible to the amateur microscopist. It is true that we have in most of our books that treat of microscopic objects, a general description of this mechanism, and if we go to the head waters and consult such original investigators as Burmeister, Westwood, and numerous others, but above all the admirable researches of M. Lacaze-Duthiers, we shall greatly extend our knowledge. Yet after having, at great expenditure of time, consulted all these and many other works, we may come back to our slide containing the dissected sting, and still find an inexplicable mystery in some of its parts. This has been my experience, and with a view of determining more accurately the entire mechanism of this intricate and complicated structure, I have carefully observed its action, so far as possible in the living insect, and by numerous dissections, in which I have traced every point of connection of the various pieces, and tested every possible movement of the parts upon each other, and made transverse sections through every point in its entire length. I now venture to place before you the result of my investigations." The article cannot unfortunately be usefully abstracted, and we can only refer to the Journal itself, of which a copy is in the library. New Diatoms.-Mr. F. Kitton sends the following: Melosira Borreri (Grev.), var. hispida, Castracane. This variety is distinguished from the type by the presence of teeth or short spines scattered over the surface of the valve, and more especially at the base of the convex part of the frustule. Canal de Trau, Dalmatia. CYCLOPHORA TENUIS, Nov. GEN., Nov. SP., OF M. DE CASTRACANE. Cyclophora, n. g.-Frustula tabulata, rectangula vel in fascias conjuncta, vel soluta, vel isthmo gelineo alternatim conjuncta, a fronte oblonga linearia, vel parum inflata; valvis inæqualibus, quarum una * M. Joannes Chatin, in 'Comptes Rendus,' vol. lxxxvi. p. 974. annulo vel loculo centrali instructa. marina. Individua vivunt in aqua C. tenuis, n. s.-Frustula a latere oblongo-rectangula, medio tumidula; valvis lineari-inflatis, polis rotundatis; una valvarum loculo centrali rotundo instructa, in sectione subquadrato. Long. valvarum, 44 μ 5-55 μ 2; lat. 4 μ 8-11 μ 3. Habitat Anconæ ad scopulum Ste. Clementis, Neapolim in aquario. μ (Atti della Accad. Pontif., 1878, 2a sess.: extracted from BREBISSONIA, No. 2, 1878-a new illustrated monthly serial devoted to Algology and Micrographic Botany, edited by M. G. Huberson.) 6 The American Quarterly Microscopical Journal'* also contains figures and descriptions by Professor H. L. Smith of the following new diatoms (all n. sp. H. L. S.) : : Homœocladia capitata.-Black Rock, Cal. Navicula parvula.-V.llerville (France). Nitzschia Kittoni.-River Catuche, Caracas, Venezuela. Amphora mucronata.-Atlantic Marshes, Cape May, N.J. In regard to the last species, the author says that its occurrence in fresh water is sufficiently remarkable, as all the members of the genus hitherto known are marine, and he concludes that it is one of those diatoms living at considerable depths, and which are only brought up by dredging or storms. That diatoms flourish in immense abundance notably, the Coscinodisceœ-at great depths is indicated by many of the 'Tuscarora' soundings; some of these, from depths of over three miles, were almost wholly Coscinodiscus omphalanthus and its varieties, fully charged with endochrome; and belts of "diatom ooze at considerable depths were also found by the Challenger' naturalists. Kutzing's Diatomaceœ.—In regard to N. Kutzingiana, Professor Hamilton Smith says: "I give to it the name of the celebrated algologist, Kutzing, whose numerous figures of Diatomaceæ, though but mere outlines sketched by aid of a microscope that would scarcely be looked at, much less through, at the present day, possess more of the character and catch more of the spirit of the living species than many of the representations of modern days, and whose descriptions are models of accuracy and conciseness. The more I study his plates, the more I admire their conscientious accuracy and faithful Collecting Copepoda. A few words as to the best modes of collecting Copepoda is given in Dr. G. S. Brady's "Monograph of the Free and Semi-parasitic Copepoda of the British Islands."† * Vol. i. p. 12. + Printed for the Ray Society, 1878. "In the case of tidal marine pools and small fresh-water ponds, such as may easily be fished from the edge, a common ring net fitted with a muslin bag and attached to the end of a walking-stick will answer every purpose. This may be worked to and fro amongst the weeds or in the clear water, and the results, when cleared from coarse debris and extraneous materials, may either be put at once into spirit, or, if it is wished to keep the Entomostraca alive, into water, fresh or salt, as the case may be. Marine surface-swimmers may be taken in a similar way by working the net from the side of a boat, or a tow net may be thrown over and attached to the boat by a cord. A tow net put overboard from a vessel anchored for the night in a tideway will often be found in the morning to have made good captures. And it may be noted that surface net gatherings made during the hours of dusk or darkness are commonly of much greater interest than those taken in daytime; it seems certain that many marine Crustacea which are found near the surface at night recede towards the bottom on the approach of daylight. . . The washing of fronds and roots of Laminariæ, which may be dragged up by means of the hooked grapnels used on many coasts by kelp-burners, often affords multitudes of Copepoda. The weeds should be washed by agitation in a large tub of sea-water, and when the operation is completed, the water, after being allowed sufficient time-a few seconds only for the subsidence of coarse material, is to be poured off through a muslin net, on which the Copepoda, and probably numerous other swimming animalcula, will be intercepted. These may be cleaned while in the net by repeated douches of sea-water. The products of the dredge, sand, mud, gravel, shells, &c., should be treated in a similar manner before being thrown overboard. I have no doubt that this method of procedure offers by far the best chance of extended acquaintance with microscopic life of the sea-bed, and that numberless new species and interesting forms of life may be discovered by its means. The preservation of specimens is probably best effected by alcohol in the form of rectified or methylated spirit, but this agent has the disadvantages of destroying many colours, and of rendering the animals opaque by coagulating their albuminous tissues. Still, among the numerous solutions which have from time to time been recommended, none are on the whole so convenient or efficient. Perhaps the next best is a solution of chloral hydrate (twelve grains to a fluid ounce) in camphor water. As microscopic preparations, Copepoda are best mounted in some gelatinous medium containing a very small quantity of glycerine. Treated in this way, mountings will keep in perfect condition for many years-eternally for anything I know to the contrary-without the trouble of cementing round the edges of the glass cover. Before dissecting Copepoda for microscopic examination, they should be macerated for a few hours in a solution of caustic potash; the fatty and granular tissues are by this means removed and the details of structure rendered clearly visible; the dissection is easily performed under the microscope with fine needles, either with or without the help of an erector." Zeiss's New Oil-immersion Objective.--Mr. A. Schulze “finds the optical qualities of this new lens in every respect equal to that of the, the angular aperture being about the same. The working distance is about one-thirtieth inch, and the magnifying power with a Ross A eye-piece fully 580 diameters. The field is perfectly flat, and the brilliancy and definition leave nothing to be desired, whilst the resolving power is extraordinary. All the finer diatomaceous tests, such as Amphipleura pellucida, &c., are resolved with the greatest ease and with the utmost distinctness; and although I have hitherto failed to see both with the and the oil-immersion lenses more than with Powell and Lealand's excellent new formula, or some other firstclass water-immersion lenses, yet I see everything better and easier than with the latter. For the resolution of the markings on diatoms no better lenses could be desired than these oil-immersion lenses. . . It is to be regretted that Professor Abbe and Mr. Zeiss deem it inadvisable to undertake the construction of microscopical objectives of yet higher power on the oil-immersion principle. This they do, however, both on account of practical difficulties in the production of still smaller lenses, and because no greater angular aperture could be gained than those of the ordinary largest angled water-immersion lenses.' ""* Theory of the Action of Bacteria in Anthrax.-In applying the data furnished by the experiments communicated to the Academy to the comparative study of the lesions which I have observed in different species of animals, I consider that it is possible to deduce from them a general theory of the action of bacteria introduced into an organism. The following is a summary of the theory: Anthrax is due to the existence of a parasite which lives and is reproduced in the blood and fluids of living animals, which acts through its physical qualities, and through the substances which it secretes or exudes, or the formation of which it provokes; these substances are soluble, and possess inflammatory properties more or less intense according to the animals which nourish the bacteria. The difference in activity of the phlogogenic matter has not yet been explained: it is possible that it depends on the peculiar properties of the blood of the animals in which the parasites are developed, but some experiments, unpublished as yet, lead me to think that they may be owing to polymorphism. When the bacteria produce a matter which is only slightly inflammatory, they act more especially by their physical properties, and cause death by the obliteration of the capillary vessels of the essential organs; such is the case with the rabbit, the sheep, and the guineapig, where these lesions are almost exclusively met with. To the more intense phlogogenic properties correspond vascular lesions of another order; the rupture of the capillary vessels and effusions of blood more or less considerable which exist simultaneously with the vascular obliterations, as is seen sometimes in sheep, and always in the horse and the ass. Lastly, the inflammatory properties may predominate, and * English Mechanic,' vol. xxviii. p. 144. death take place, when the number of the bacteria is relatively inconsiderable; the vascular ruptures then become of extreme importance; they are found especially in the walls of the heart of the dog. It now remains, in order to complete this theory, to examine and explain the lesions of the lymphatic system. The following are the facts which have been derived from my experiments: Three cases are possible: 1. The Anthrax was transmitted by inoculation to an animal which died without showing vascular ruptures. 2. The Anthrax was transmitted to the animal by injection direct into a vessel. 3. The Anthrax was transmitted either by inoculation or by intravascular injection to an animal which in the course of the malady showed more or less numerous vascular ruptures. In the first case researches made on the fresh or hardened ganglia and by means of sections, showed no bacteria except in those situated in the course of the lymphatics, proceeding from the inoculated spot, where they were found in immense numbers. In the second case no ganglion showed the presence of bacteria in the sinus; the only ones met with were contained in the blood-vessels of the follicles. In the third case all the ganglia situated in the course of the lymphatics, proceeding from the points where the vascular ruptures existed, were gorged with bacteria; the infiltrations in the neighbourhood of the rupture showed heaps of them, formed of long entangled filaments, and the ganglia had a quantity of them in their sinus, which augmented with the age of the rupture. These three cases are easily interpreted; they are reducible, in fact, to one. The mode of action of the bacteria is always the saine. Take the first (that of inoculation) as a typical case. When an animal has been inoculated, from that moment until its death it constantly shows the presence of bacteria in one or other parts of its economy-not latent bacteria in the state of the germ, but entire and articulated, and visible to the microscope. They are always found in the connective tissue adjacent to the inoculated spot, and their number is greater in proportion as the period of inoculation is distant from that of observation. The infiltration or oedema which they provoke, is propagated in the direction of the lymphatics which collect and convey them to the ganglion. They penetrate this organ, as do all finely pulverized solid substances, as red-lead injected under the skin and tattoo powders; I have found them in considerable numbers (about ten in the field of the microscope), five hours after an inoculation has been made, at two centimetres distance from an axillary ganglion, in the pulp of this ganglion. Once in a ganglion they multiply, produce inflammation, and a more ready discharge of the substances inclosed in the lymphatic sinus; their multiplication by elongation is also a mode of progression; they finally issue forth through the efferent vessels and reach the following ganglion, or rather the blood-vessels, where they multiply rapidly and where they remain. |