Ulota phyllantha, Brid., is an interesting moss. It grows upon trees and rocks, and is sometimes very abundant; at least, in certain places-in Antrim, Down, Armagh, and Tyrone, It forms dense green tufts that are sometimes ferruginous from the masses of spores borne in the thickened tips of the nerves. As the plants become crisp when dry, they present in that condition a very different appearance to what is seen when they are moist. The fruit of this moss has never been met with; in fact, it is not known whether it produces any. Reproduction is provided for by the multitudes of gemmæ, or buds, which are borne on the tips of the leaves, as shown in Fig. 2, Pl. V. The gemmæ are cylindrical, articulated, and of a rusty brown colour, and if it was not known what they were, the plant would be handed over to the Lichens, to one species of which (Autographa elegans) they bear a striking resemblance (see b, c, Fig. 2). The propagation of mosses by means of gemmæ is a very interesting study of itself. There are many mosses which bear no fruit, and yet multiply rapidly; e.g., Eucalypta streptocarpon has never been found in fruit in Ireland, and yet there it grows most plentifully, and this is a moss which, if it has gemmæ, like Ulita p. or Aulacomnion androgyneum, they must disappear very quickly, as I have not been unable to discover them. H. W. LETT, M.A. EXPLANATION OF PLATE IV. Fig. 1.-Stigonema saxicolum, Naeg., × 180. 2.--Lemanea fluviatilis, Ag., × 85; b, same, × 180. PLATE V. Fig. 1.-Fusisporium aurantiacum, Lk., x 250. IT 2.-A, Ulota phyllantha, × 20; B, Gemma of do., x 100; c, Spore of Lichen, Autographa (Opeographa) elegans, × 250. Drawn by H. W. Lett, M.A. NOTES ON FINISHING SLIDES. 66 mounts BY MAJOR T. A. SKELTON. (Lower Portion of Plate V.) T will, I think, be generally admitted that good deserve good "finish," and it is certainly true that careful and good "finish" ensures better protection to the mount than a careless, rough ringing, and any excuse for offering these observations must be that sometimes truly good and beautiful slides are circulated with evident disregard to "finish," both in security and appearance. The tools and materials requisite for successful finishing of slides are: A TURN-TABLE, with means of accurately centering the slide. A LARGE NEEDLE set in a handle, and filed and sharpened to a chisel-like point. A LARGE CAMEL-HAIR BRUSH, for use as a dusting-brush. ONE BOTTLE OF BROWN VARNISH. I use "Miller's Catchu Cement." ONE BOTTLE OF ZINC WHITE VARNISH. ONE BOTTLE OF BLACK VARNISH. SPIRITS OF WINE (Methylated). I use "Black Enamel." RECTIFIED PURE BENZINE (or BENZOL). It is of the utmost importance to have clean and new materials, and good brushes kept perfectly clean. Always wash them well-first in benzole and then in soap and water immediately after using. The three small brushes must be sable, as camel hair is not firm enough for these varnishes. Mark these brushes, one for each material. Do not pour out the varnishes, but dip from the bottle. Keep the varnishes well shaken or they will settle. Keep them thin by adding benzol when required. Do not let the brushes get dry while you are working, but lay each in a separate small cup of benzol, and wipe them clean on paper before dipping into the bottle. HOW TO PROCEED WITH THE MANIPULATION. 1st. Take your slide in the rough state when the balsam is hard (Fig. 1, lower portion of Pl, V.), and with the chisel-pointed needle cut and scrape all outside the cover-glass; wipe off the chips and dust, and then with a soft rag, moistened with methylated spirit of wine, wipe the slide clean, as Fig. 2. 2nd.-Place the cleaned slide on the turn-table, centre it, and carefully ring it with brown varnish, not using too much material, and only just lapping on to the face of the cover-glass. See that the angle at the edge of the cover-glass is fully flushed up to the level of the face of the cover (see Fig. 3); then remove it and leave till dry and hard-this may be a week or more. In this state when hard, the slide may be washed, cleaned, and polished. Avoid using spirit of wine, as that will dissolve the brown varnish. The slide is now safely protected, and duplicates may conveniently be kept in this condition. 3rd.-Place the slide on the turn-table and centre the coverglass most carefully; perfect finish depends on the perfect centering of the cover-glass. Take the chisel-pointed needle, and with it turn the brown varnish into even shape and surface as Fig. 4; but on no account remove it from the turn-table, or you will have great difficulty in replacing it exactly. 4th. Now brush off with the large camel-hair brush quite clean of dust, and then with the small sable-brush and very little thin zinc white varnish mark the inner and outer margins of the intended white ring, and immediately, with a fairly full brush, fill in between and flush-up the ring full and evenly (see Fig. 5). Be quick and finish the ring before the varnish sets,' or you will raise irregularities on the surface-(if that occurs, a very little benzol in the brush will get over the difficulty, but do without it if possible). Wait about three minutes, and then with a small brush and very little black varnish or "enamel" put a black ring (as in Fig. 6) over the edge of the cover-glass, which generally shows through the white ring. This requires practice and judgment, as, if done too soon, the black will run and spread into the white, and if too late it may be irregular, raised, and will perhaps easily chip off. 5th. If the slide is desired to be plain black, use black enamel instead of the zinc white varnish, as described in Fig. 4. 6th. Coloured rings and markings may be put in place of plain white and black; this is a matter of taste only. I prefer and advise a plain single black ring on a white ground. 7th. When the cover-glass is mounted on a ring, use black enamel only. It is very difficult, if not impossible. to finish satisfactorily in white and black; in fact, the thinner the mount and cover-glass, the neater the finish can be. 8th. It is a good plan to have before you a well-finished slide of a "professional" mounter, such as the slides sent out by Mr. A. C. Cole, and to endeavour to imitate its perfection. And it is well to prepare and finish a batch of a dozen or so (stages 4, 5, and 6) at a sitting. These hints, from my own experience, are given in full detail, in the hope that they may be useful to others, and because I have found the brief directions published in books of little use to myself as a beginner, and I trust others will add further hints from their experience for our mutual benefit. ADDITIONAL NOTES. With reference to the above remarks on finishing balsam mounts, my own opinion always has been, "Why ring balsam mounts at all?" I consider a slide, as Fig. 2, quite sufficiently finished for all ordinary purposes, and life is too short to do more to an ordinary balsam mount than clean it with cotton wool dipped in methylated spirit. If the balsam is not quite hard, any varnish will have a tendency to run in. The balsam must, therefore, be hardened by putting the cover-glass between the claws of two pressureless mounting-clips for protection, and placing the slide on a hot-water cistern or similar place. If the balsam is hard, what need is there for further protection? I am only speaking for those who, like myself, have no time to give to finishing their slides elaborately. There is another alternative way of giving slides a good finished appearance—viz., by having rings of coloured paper punched out, and sticking them down over the edge of the cover. Of course, they are not so neat as the varnish, but they will take less time to do. For dry or fluid mounts, finishing is, of course, indispensable. I would also suggest that when slides are finished, each mounter should choose some particular colour or colours for the varnishes as his "trade-mark." GEO. H. BRYAN. I am sure the thanks of the Society, and especially of the junior members, are due to Major Skelton for his notes on finishing slides, for with all deference to the utilitarian views of some of our members, it seems to me an object that has been worth the trouble of mounting is also worth the trouble of neatly finishing, and presents thereby a much more pleasing appearance in the cabinet. Of course, when objects are thin-such as sections a slide may be considered sufficiently neat when the superfluous balsam is cleaned away without anything further being done to it; but when objects are mounted without pressure, and the cover-glass supported on fragments of glass, or glass beads, the neatness of appearance of all varnishes, and the ringing of the slide becomes a necessity. In cases such as these, it is better not to remove the superfluous balsam (see Fig. 7), as it leaves too great an angle to be properly filled up by the zinc varnish readily; but if the balsam is bevelled away all round (as in Fig. 8), the cover-glass is more firmly fixed, and the varnish makes at once a satisfactory finish. When such deep mounts are left unfinished, there is a tendency for the whole thing to be disturbed by any accidental jar. Provided the slides are left long enough for the balsam to dry sufficiently, the brown-varnish process may be omitted, and the zinc-white cement at once applied without the preliminary tracing of the two rings. By using a particular colour-ring for special objects, such slides are readily distinguished from others in the cabinet, and this is an arrangement I have long adopted with my own. E. BOSTOCK. [A few additional notes relating to this subject will be inserted in our next.-ED.] I Motes. T has been proposed to us that it would be of great interest if we were to publish a List of all the Microscopical Societies and Clubs in the United Kingdom, (including those Societies that have Microscopical Sections), together with the Secretaries' names, rules of admittance, subscriptions, organ of publication and price of same, with other particulars. To make the list complete, we must ask our readers to co-operate with us in the matter. If they will kindly forward any information they may possess with respect to the Microscopical Societies, etc., in their districts, we shall be extremely glad to incorporate it with the list we have already drawn up. The writer of a paper that was read at the R.M.S. in June last created some surprise by declaring that, in his belief, the Continental form of stand was gradually ousting the English pattern out of the market. In apparent contradiction to this, we have lately had the pleasure of examining a microscope by Herr E. Leitz, of Wetzlar, that has been made on the English model. The foot is that known as the "bent claw" shape, popularised by Messrs. Swift and other opticians, and Herr Leitz has also adopted Mr. E. M. Nelson's horse-shoe stage. We venture to suggest that it would be a great improvement if the mirror was not on the same bar as the condenser. At present, if artificial light be used, one is practically debarred from using the condenser after once focussing, as the slightest movement puts the mirror out of range. By cutting off the condenser-bar close to the rackwork and by lengthening the tail-piece, we believe this essential improvement could be easily effected. We understand that the Trustees of the British Museum have lately acquired the magnificent collection of Diatoms formed by Mr. Julien Deby, F.R.M.S. This collection, which is undoubtedly the finest in existence and contains many type slides, is now open for reference by students in the Cryptogamic Herbarium of the Natural History Museum. The Museum collection of diatoms is now estimated to amount to about 50,000 slides. We hear that it is intended to form a permanent Museum in Chicago, and that Prof. F. W. Putnam is to be the director. The museum will probably be located near the University. With such a city and with such a director, we shall expect that Chicago's museum will be one of the best museums in the States. A good nucleus will probably be formed from exhibits in the Columbian Exhibition, as there is much there that can probably be had for the asking. |