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Proceedings of Societies

1866; The Company of Biologists; Volume: S2-6; Issue: 21 Linguagem: Inglês

10.1242/jcs.s2-6.21.53

1477-9137

Glaisher James,

Genetics, Bioinformatics, and Biomedical Research

Mr. Roper read a communication received by him from the Royal Society of Tasmania, and added that copies of the “Transactions “of that Society had been transmitted and would be placed in the library.The Secretary stated that there were no papers to be read. He also announced the resignation of the late Curator of the Society, and the appointment of Mr. Evans to that office. The members were requested to return to the Secretary all books, <tc., belonging to the Society, in order that a proper account might be taken of the Society’s property. With reference to papers to be read at future meetings the President suggested that he should be informed beforehand of their subjects, so that notice might be given in the ‘Athenæum,’ and otherwise, thus giving gentlemen qualified to discuss them the opportunity of coming to the meetings properly prepared.Mr. INCE called the attention of the Society to some diseased wheat from Droxford, Hants. It was grown on a field of three acres and three quarters, and the crop was so seriously damaged that the whole sold for only 6. He hoped by thus bringing the matter before the Society to elicit some information as to the nature of the disease in question.Mr. SLACK said—If I had known that there were no papers to be laid before the Society this evening, I would have brought and shown to the Society the new form of spectroscope I received, a few days ago, from Mr. Browning. I expressed at the last meeting a belief that the best spectroscope would be a direct vision one. I thought that looking round a corner was an inconvenient thing for microscopists to do, and if a spectroscope could be arranged to pull in and out with facility, and capable of being adjusted with nicety, it would be highly appreciated. Now Mr. Browning has been experimenting with Mr. Sorby for some time on a spectroscope which is being brought out, and I believe he calls it the “Sorby-Browning spectroscope.” It is a few inches long, contains an eye-piece, and between the two lenses of the eye-piece there is an apparatus for adjusting the slit. You can adjust the slit in the usual way by a side screw, so as to get any amount of opening you like. You can further adjust a vertical shutter up or down the slit, so as to reduce the limits of the spectrum in that direction. That you can form a little cage in which small objects can be optically placed, and isolated from all surrounding objects. The prism fits on the top of the eye-piece, which carries the slit and other apparatus, and indeed very much in the same way in which you can put the analysing prism of a polariscope on the top of an ordinary eye-piece. By removing the prism or opening the slit you look through the two lenses of the apparatus which constitutes an eye-piece, through your object-glass, and see the object that you have in the field. You can then bring any portion you wish into the centre of the field, and adjust the dimensions of the field, if necessary, in two directions, and obtain your spectrum either by transmitted light, viewing the object as a transparent one, or by reflected light, viewing it as an opaque one. There is also a provision for sending a second beam light through the prism, it enters on one side, strikes against a little right-angled prism, and passes through the slit to the chief prism: thus you can easily get two spectra for comparison, at the same time, in the field. The general arrangement of the apparatus carries out the ideas that were expressed in this place, by Mr. Wenham and other gentlemen who have discussed this subject. Historically speaking, I believe the matter stands thus: To Mr. Sorby belongs the merit of introducing this kind of investigation, and he applied it at first exclusively to small quantities of fluids contained in cells. Mr. Huggins then sent in a paper which was read a meeting or two back, and Mr. Wenham made some special remarks on it. That paper and Mi’. Wenham’s observations called our attention to the importance of obtaining the spectra of opaque objects, and to the very curious fact that some mineral and other objects yielded mono-chromatic light, while others were deficient of the rays they might be expected to possess. I saw, and others who are here also saw, a card with a small drop of dried blood upon it, and I was told that Mr. Sorby had obtained an excellent spectrum from that object. Now, in this instrument of Mr. Browning’s these things can be accomplished with very great ease; you take an infinitesimal quantity of blood, and you may either view it as an opaque object when dry, or as a transparent one, and you can immediately detect its characteristic spectrum. Remembering the hint of Mr. Wenham, I took a small quantity of fresh blood, and viewed it under Messrs. Smith and Beck’s excellent j5th. I isolated a single globule, closing the slit horizontally and vertically, so that there was no other globule in the field. I immediately got, as Mr. Wenham said we should get, a beautifully characteristic spectrum with the two distinct dark bands indicating blood. This form of spectroscope can. be placed under the stage when it is required, but it is my present opinion that this will not be a very frequent mode of using the instrument. It appears to me that the plan of putting it on as an eye-piece would in the majority of cases be most convenient. When you have an ordinary-sized drop that would fall from a bottle of any such fluid as anfline-dye, you do not want an object-glass at all, as you get its spectrum clearly without. If you operate upon a good-sized drop you can do it very well with a three inch or two inch povyer; if you take a very small drop such a power as a three inch would be convenient, and with a smaller quantity you may work with as high a power as Messrs. Smith and Beck’s th, or even with Powell’s th. I found a very convenient mode of operation to be, to put a glass stage upon the microscope with a rim all round so as effectively to prevent corrosive fluids from running over, and, if I had one made on purpose, I should make the bottom rim stick up a little at an acute angle. If you take a little piece of glass tube and draw it out to the size of a needle and turn it round the corner, like the crook of an umbrella, you can hook up a small quantity of fluid and transfer to the glass stage a drop so small as to have no chance of falling down, aud which will yet last several minutes without disappearing from evaporation. I find that in this way a series of minute experiments could be carried on with great facility. The union of spectroscope with microscope opens a most interesting range of inquiry, and not the least interesting result, in one point of view, will be the getting a better notion of what the colours of certain objects really are. It is well known that we can take two solutions which are very nearly alike to the ordinary eye and are perhaps undistinguishable by it, and yet the spectroscope discriminates them at once. I apprehend that when we view an object—a transparent or an opaque one, as the case may be—the spectroscope shows us precisely what our eyes would show us if they were more exact; and it is interesting to know exactly what rays are deficient in particular colours, and also to see how the application of small quantities of different reagents can effect such molecular or chemical changes as to change the spectrum.Mr. Slack did not know, when making those observations, that some of the new spectroscopes were in the room.The PRESIDENT announced that several microscopes to which the Sorby-Browning principle was applied were in the room for the inspection of the members.Mr. LOBB gave an account of a vacation visit to Oakshott, near Leatherhead, in Surrey, and to Keston, near Bromley, in Kent., At Oakshott he had found in a spring on the heath great abundance of Closteria, with scarcely any admixture of other genera. The gathering was exceedingly pure. At Keston he had obtained Desmidiaceæ of almost every genera and species figured in Ralfs: among them he had discovered what he thought was a new species either of Cosmarium or Staurastrum; there was, however, a difficulty in deciding which. The frond has conic spines round the edges, each segment being full of granular endochrome, surrounded with thickly-set hyaline rays extending to some distance beyond the segments, similar to those of Actinophrys Sol, but far more closely set together; between the segments the rays extend in a straight line, the frond having something of this appearance. Should it be a new species, Mr. Lobb thought it might not be inaptly named Oosmarium radiatum.JABEZ HOGG, Esq., F.L.S., read a paper entitled “Further observations on vegetable parasites, particularly those infesting the human skin.” (‘Trans.,’ p. 10.)Dr. HUNT said: Mr. President,—As Mr. Hogg has very kindly mentioned my name in connection with his paper, I take the liberty to rise for the purpose of making a few remarks upon it. The subject of skin diseases is not attractive to those who are not engaged in medical practice. It is one of those departments of nature which illustrates (and in a very important manner) certain laws of nature. I think in the paper read tonight there is involved a very important question, viz.: the question relating to that law of nature by which Providence prepares a remedy for all physical evils. “Wherever there is a decay nature immediately prepares some animal or vegetable structure to remove the decayed matter. That we are familiar with from the carrion crow to the mites in cheese. “We know that decay or even death cannot be, but there must be some animal or vegetable designed by Providence to carry away the dead or decayed matter. Now, from my experience in skin diseases I may say that they all tend to produce decayed matter on the surface of the body, and this matter is sometimes situated too deeply to be cleared away by ablution. Here Providence has prepared the parasite to eat it away or to be sown into, and, so to speak, nourish it away. Where the parasite is vegetable there is a soil produced; in that soil the parasite thrives, and it carries away the soil until at length, in many cases—the common ringworm for instance—though nothing is done to remove it, the whole soil is after a few years absorbed by the parasite, and the disease is cured by the parasite—cured by its own agency irrespective of the physician. Now, there is a tendency in all diseases to be cured by nature. There never was a fever or any other disease in which there was not to be found (if you would search for it) an effort of nature to remove that disease. We are apt sometimes to be blind to this; but, if we have anything to do as medical men, it is to find out what nature is doing to assist nature when she seems feeble, and to check her when she seems to be doing too much—for, strange to say, nature often does too much. Sometimes to relieve inflammation she produces gangrene; gangrene would destroy life, and therefore we must cut off the gangrene. Sometimes parasites do too much, and, as Dr. Tilbury Fox has rightly remarked, they produce disease; but they do not originate disease, for disease always originates them. I deny that the so-called new class of diseases called parasitic diseases are a class at all, and I demur to the term altogether. If the term means that diseases are produced by parasites I deny it in toto. The disease forms the anides, a soil or food for the parasite, and the parasite comes to feed upon it; the disease is there before, or the parasite could not be there. But then, if what is meant by “parasitic diseases “is that they are not diseases produced by parasites; that they are diseases attended by parasites, incidentally or accidentally, then I maintain that there is no distinction, for every disease is accompanied by parasites. There never was a disease of animal or vegetable matter that was not attended by parasites, or for which some parasite has not been prepared to carry away the results of the disease, and it is only because we shut our eyes to one half of nature while we are dreaming of the other half that we do not see these things plainly. It is a law of nature that Providence sends no evil in the shape of a disease for which it does not send the remedy; and, therefore, I am sorry to have observed that many clever men both here and abroad have taken upon themselves to say that there is a distinct class of skin diseases produced by parasites. They might as well say that there was a distinct class of eye diseases, of brain diseases, or nose, or any other diseases. These diseases, in common with all others, are attended with parasites, as may be frequently discovered by the microscope, which is nothing but a peep into nature. He concluded by stating that if any of the members were desirous of examining the parasitical products of skin diseases, he should be happy to afford them two or three hundred cases a week.Mr. SLACK said — In some prolonged examinations of the vinegar plant made under various circumstances, I have found nearly all the forms of cells which Mr. Hogg has described as resulting from the spores or cells generated by certain peculiar forms of disease. I paid some attention to the development of these fungi, and I was exceedingly pleased to find so distinguished an authority making havoc among the numerous species of these minute bodies. 1 think it would not be without interest if the members would get so easily obtainable a thing as a vinegar plant, and, by growing it under different conditions, find these different cells all associated with a great quantity of bactrium cells as they appeared in one of Mr. Hogg’s experiments. I think that experiment confirms the opinion I have expressed, that when a large quantity.of bactrium cells are associated with yeast cells, the acetous fermentation appears to set in.Dr. VARLEY explained the curative effect of carbonic acid gas in certain diseases, and detailed the method of application as pursued by himself and his late uncle.The PRESIDENT, after some remarks on the importance of the microscope in pursuing medical inquiries, proposed a vote of thanks to Mr. Hogg and Dr. Hunt, which was carried with applause; and announced that the former had promised to present to the Society a number of specimens illustrative of his paper.The PRESIDENT announced the receipt of a paper from Dr. Greville, on “New and Rare Diatoms.” (‘Trans.,’ p. 1.)Mr. Archer exhibited, from a gathering made near Euniskerry, a number of globular, densely spined bodies, with green contents, the spines very numerous, very slender throughout, and acute. These bodies were generally to be found distributed in pairs over the field, and they might easily at first sight be taken for so many zygospores, of some Desmidian; but, much as such a structure resembled a possible zygospore, these bodies were not like that of any known Desmidian, nor was there any evidence in the gathering that they might actually be zygospores of any form not yet known in the conjugated state. Hence, but for an observation made by Mr. Archer on a previous occasion, the source of the curious bodies now exhibited would have been not a little puzzling.In a gathering made (not. however, from the same locality) during last year, Mr. Archer had taken a quantity of the rather common Desmidian, Penium digitus, and a number of these showed, some individuals one, the majority two, and a few three, quite identical stellate bodies in the interior of each cell. These were evidently formed at the expense of the cell-contents of the individual Penium in which they occurred. Some of these showed the cell-contents partially absorbed, and the remainder dead and brown; whilst others did not exhibit a trace of the original contents, but contained the (generally) two stellate bodies, green and vigorous, one in each half of the old cell-wall of the Penium which still enveloped them. But afterwards these bodies might be found without the encompassing old membrane of the Penium, and usually distributed in pairs over the field.Now, although in the present instance Mr. Archer was unable to trace back these spinous bodies to a Penium, their identity in appearance in every way, and the fact of their having been found distributed in pairs (as if left behind, as Mr. Archer had seen on the previous occasion, by the decayed or dissolved outer wall of the Penium), seemed to point out that, be their nature what it might, these bodies were in both instances one and the same thing, and that in the present instance, like the former, the spinous bodies exhibited owed their origin to Penium digitus.These bodies were, in fact, the “ásteridia “of the Penium, to adopt Thwaites’ term as applied to the stellate bodies occurring within the cells of other Conjugate, and, like such similar bodies, must probably be regarded as parasitic growths. These, indeed, were altogether unlike the smooth, rounded, or irregularly shaped, opaque, brownish spore-like bodies, often seen iu various Desmidiaceæ, whose nature continues equally problematical. In the present instance, in regard to these bodies, though with green cell-contents, like other asteridia, the fact of the cell-contents of the original Penium becoming mostly all absorbed—if not quite all absorbed, the residue becoming quite effete and brown— seems to speak for their parasitic nature.But besides the spinous bodies, Mr. Archer likewise drew attention to anumber of slightly smaller, globular, green and smooth cells lying over the field, in some of which a directly transverse well-marked light line could be seen, indicating a commencing selfdivision. A few of these bodies might be seen loosely invested by a colourless coat, externally covered by slender spines; these loose external coats stood off from the inner spherical, smoothly bounded bodies, the whole somewhat like the doubly bounded spores of Volvox glolator before these assume the golden hue— that is, of course, excepting the fact that in the latter the outer coat, as is well known, is then destitute of spines. These loose outer coats permit the escape of the definitely bounded inner smooth cell by the rupture of the former by a large rent. After escape this body, in some measure, called to mind, as before mentioned, the still green inner spore of Volvox, or a very small specimen of Eremosphæra viridis (De Bary), but any one acquainted with these forms would at once recognise that it was neither the one nor the other that he liad before him. It is possible that some of these smooth green bodies may have originated from the Penium, and never had a spinous coat developed. In a small form of Mesocarpus (which, not being conjugated, could not be identified) Mr. Archer had lately seen a number of minute stellate bodies (“asteridia “) similar to those not infrequently seen in Spirogyra, but with fewer and longer spines. But wfiat makes that circumstance more especially worth noticing is that he had observed the slipping out of the smooth inner cell from the spinous outer coat by a rent, and this taking place still within the joint of the Mesocarpus; he had not, however, noticed any evidence of any further growth or of a self-division. Be, then, the nature of these curious bodies in the Penium, in the Mesocarpus, or the more common similar growths in Spirogyra, what it may, it is at least highly probable that they are all analogous structures, and, in our present want of knowledge as to their true nature, they must remain “asteridia.”Mr. Archer likewise exhibited a Cylindrocystis (Menegh.) as yet undescribed, and for the purpose of comparison and contrast placed side by side therewith, under other microscopes, specimens of Cylindrocystis Brébissonii (Menegh.) and of Cylindrocystis crassa (De Bary), when the absolute distinctness of all three species was readily apparent; and not only was their distinctness striking when viewed microscopically,but the difference in their appearance in the mass to the unassisted eye was abundantly evident. The present plant Mr. Archer had as yet seen only in one locality, near Lough Bray, and there in several pools he had noticed it for three years past, but he regretted that, although he had annually taken specimens, he had not as yet been fortunate in finding this species conjugated. This plant formed a red stratum at the peaty bottom of the shallow pools, of some two or three inches in depth. It was greatly narrower and greatly longer than C. Brébissonii, the ends truncate, and a microscopical examination showed that its red colour was due to the tint of the cell-wall, and not to that of its contents. In this year’s gathering it was mixed in some pools with C. Brébissonii, but these two very distinct plants side by side maintained their own characteristics absolutely. When Cleve’s name, Penium rufescens, for a new species (in ‘Ofversigt af Kongl. Vetenskaps-Akademiens Forhandlingar,’ 1863, p. 493) first caught his eye, Mr. Archer imagined that the red colour rendered it likely that these two plants were the same, but an examination of the description and figure sets the point at rest— they are absolutely distinct, and could never be mistaken the one for the other; besides, Cleve admits the genus Cylindrocystis as distinct from Penium, thus precluding the likelihood of his describing the plant now exhibited (if, indeed, he had found it) under the latter genus.Captain F. W. Hutton then brought under the notice of the club a small pair of forceps, manufactured for him by Messrs. Yeates aud Son, 2, Grafton Street, Dublin, tobe used in connection with Messrs. Smith and Beck’s “opaque-disc-revolver.”He had found, when using the discs as supplied with the revolver, that great inconvenience resulted from having either to fasten the object on to the disc with some sort of cement, or else to place it in a drop of water to prevent its slipping off when the disc was inclined at an angle with the horizon. For practical working purposes both of these processes are very objectionable; the first on account of the time it takes and the trouble in changing the object, the second on account of many parts of the object being covered by a film of water with rounded surfaces, which completely alters its appearance, and also because when the object is under examination for some little time the water dries up and the object suddenly slips out of view, perhaps, in the middle of an observation.To remedy this he asked Mr. Yeates last autumn to make a small pair of forceps to fit into the hole in the “revolver “like an ordinary disc, which he succeeded in doing, and which Captain Hutton had found to answer his purpose perfectly.In construction it is very simple, and will be readily understood from the accompanying figure, which represents a section of the forceps drawn about four times the natural size, in order to make it clearer; the shaded portion representing that part of the “discrevolver “into which the forceps fit, the unshaded part the forceps themselves.a b Is a disc of brass of the same size and shape of the discs upplied by Messrs. Smith and Beck, a round hole of the same size as the hole in the “revolver” being drilled through the centre, a d Is an arm of the forceps fixed firmly into a b, and has a longitudinal groove cut in the inside, into which the movable arm e f fits, and turns on the pivot g. The lower part of the groove is occupied by a small spring (Ji) which keeps the points of the forceps closed.The pivot should be placed below the disc so as to admit of the points of the forceps being brought as near as possible to the upper surface of the disc, and yet allow them to open sufficiently wide to be practically useful.He found that if the points of the forceps project about an eighth of an inch above the disc the whole of an object held in them (except, of course, that part actually covered by the forceps) can be viewed with a -j-inch object-glass without any difficulty.The advantage of this little piece of apparatus will be obvious to any one who has fumbled for half an hour or more over a common pair of forceps, a pin, and a piece of cork, without, perhaps, in the end obtaining a good view of his object in the required position. But it has more important uses than simplifying manipulation, for it enables the same specimen to be viewed and drawn in any number of positions and aspects, while by the old method several specimens must generally be employed when different views are required, on account of the difficulty attending the taking of a minute and delicate object out of the forceps and replacing it in another position without damaging it, thus often, perhaps, leading to error.Mr. Woodworth showed a considerable number of excellent photographs of microscopic objects on various enlarged scales; amongst these were tongue of cricket, saw of saw-fly, jaw of spider, butterfly scales, &c., &c. These all showed the minute structure beautifully. Mr. Woodworth stated his intention to continue his experiments in this direction.Dr. Moore showed illustrations of Dr. Seemann’s characters for distinguishing the British, Canary, and Asiatic species of ivy, by the hairs on their calycine segments and petioles of the flowers. The common ivy, with its varieties, were shown to have the hairs with eight rays, which is very constantly the case. The hairs on Hederá Canariensis have as constantly from eleven to fifteen rays; whilst the Asiatic ivy, Hederá colchica (Koch) has the hairs on the calyx and pedicles in two-lobed scales, each lobe having from seven to ten rays. Dr. Moore, however, stated that he could not reconcile his views with those expressed by Dr. Seemann, in considering the large-leaved ivy, cultivated as Hederá Rœgneriana in gardens, and the very rare, small-leaved, yellow-fruited one from the Himalayan Mountains, Hederá chrysocarpa (Wallich), being states of one species.Dr. Moore drew attention to the rapid growth in the Victoria Tank, in the Botanical Garden, of a species of Spirogyra, seemingly & longata. In eleven days, since the tank was filled, this plant had covered surfaces of many feet.Mr. Archer further exhibited some rare minute algæ, amongst which were Œdogoniwm Itzigsohnii (de Bary) in fruit (vide de Bary, ‘Ueber die Algengattungen Oedogonium und Bulbochæte,’ p. 56, t. iii., f. 29-32). This minute species Mr. Archer had picked up several times, and often showing its peculiarly-lobed oogonium, but he had never found the male fructification; he believed the plant must turn out to be a dioecious species; he had sometimes noticed a minute notch-like depression on the upper outer margin of the oogonium, probably indicating the “micropyle.” He drew attention to the character, not adverted to by de Bary, that the apical or terminal joint of the filament possessed a short acute spine or mucro. This, in old plants, frequently is not to be seen, as the terminal joint, or, indeed, considerable portions of the filaments, often become detached, and chiefly in a young condition only are the plants found entire.Mr. Archer likewise showed specimens of Leptocystinema Kinahani (ejus). This well-marked plant he had but once found since he ventured first to describe it (‘Proceedings of the Dublin University Zool. and Bot. Association,’ vol. i, pp. 94, 105; also Nat. Hist. Review,’ O.S., vol. v, p. 234.) The present specimens were gathered by Captain Hutton on a late visit to the County Donegal, and kindly given to him by that gentleman. Mr. Archer had never seen this plant conjugated, but, beyond doubt, it must so reproduce itself, and it would be interesting to note any minor peculiarity which it might present during that process.There was also shown by Mr. Archer the form called Pleurococcus superbus by Cienkowski (see ‘Botanische Zeitung,’ No. 3, Jan., 1865, p. 21). He likewise exhibited Ophiocytiwm apiculatum (Nag.) and Polyedrium, tetraedricum (Nag.).Dr. Moore exhibited a Sirosiphon== ZZh.s.?izZ/za compacta (Hass.).Dr. Moore also showed specimens of Chroolepus Arnottii, obtained by Admiral Jones in Scotland. Dr. Moore had himself taken this plant in Ireland, but he regarded it as very rare.Mr. Archer mentioned that Admiral Jones had kindly given him a specimen of the plant shown by Dr. Moore. Mr. Archer had never met it near Dublin, and could only refer it to Chroolepus, but was afterwards informed by Admiral Jones that it was C. Arnottii. In looking over the specimens Mr. Archer thought he could perceive the torulose filaments formed by this plant to be accompanied by slender cylindrical filaments, attached to the former, and apparently of the same nature as those appertaining to Chroolepus ebeneum. Now, in this latter Mr. Archer was quite disposed to regard these accompanying filaments as part of the organization of the plant, as he had mentioned at the meeting of the club on the 19th January last; and it seemed to him at least probable that here, too, they bore a relationship to the torulose filaments corresponding to that of the similar threads in C. ebeneum; that is, that O. Arnottii may be, in truth, when found in fruit, proved to be a lichen, the slender accompanying threads representing the fibrous element in a typical lichen, and the torulose filaments themselves, here the marked and conspicuous part of the plant, the gonidia! element. This, of course, until one or both of these plants be found in fruit, is but a conjecture, but one not without foundation, as Cœnogonium, in its fruit a true lichen, is quite as aberrant in its thallus, the structure of which latter seems essentially to agree with that of the plant under consideration.Dr. Moore exhibited the seeds of Disa grandiflora by reflected light. The reticulated outer skin of these formed very pretty objects.Mr. Archer showed fine specimens of Sciadium arbuscula (Al. Braun) new to Ireland. This remarkable little alga had been recorded from several localities on the Continent,