perhaps very faintly in one or two instances, in any other species of Agaric. There is, however, a Lactarius which resembles an Agaric in form, but contains a copious supply of white milk somewhat acrid to the taste, and an odour not much unlike but rather more camphoraceous than the two Agarics. This is Lactarius glyciosmus, which has a reddish-cream colour when dry, but is more ruddy when moist. In addition we may mention a densely tufted fungus growing on stumps, Lentinus cochleatus, with a fainter but similar odour to the Agaricus odorus. One species of Hydnum, in which the gills of the hymenium are replaced by spines, has but a faint smell of melilot when fresh, but in drying this odour is intensified, and remains persistent for three or four years. This is known as Hydnum graveolens, but is somewhat rare in Britain. Finally, we have two species of woody Trametes, found growing on trees, which possess an odour of the same type. These are Trametes suaveolens and Trametes odora, and quite resembling them is Trametes inodora, which has no distinct odour at all. The chemical character of this odour has never, to our knowledge, been investigated, but the point now in question is the reason for its existence, and for this all conjectures hitherto offered are weak. In several of the fragrant species it will be remembered that there are similar and allied species which have no perceptible odour; it is possible that this fact may have some value in the investigation.

Passing over other types of odour which prevail in fungi, we will take as a final example a pungent odour as of nitric acid, which is by no means uncommon. It is rather rare with white-spored Agarics, but is often met with in pink-spored species, many of which are either doubtful or poisonous. The majority of instances amongst white-spored species will be found in the subgenus Mycena, wherein the species are small and delicate, such as Agaricus (Mycena) alcalinus, and Agaricus (Mycena) ammoniacus, to which may be added also Agaricus (Mycena) metatus and Agaricus (Mycena) leptocephalus, although in a less degree; but the culminating examples will be found in the Hyporrhodii. One of the commonest of woodland Agarics in the autumn is Agaricus (Entoloma) nidorosus, which the nose will always determine if the eyes should fail. It is a pale mouse-coloured species, generally about 2 or 3 inches in diameter, which the odour would be sufficient to deter anyone from feeling desirous of tasting, if it had not also a very suspicious appearance. It may be taken for granted that where this odour prevails the species are not edible, even should they escape being positively poisonous. There is a suggestion of the same odour in Agaricus (Hebeloma) elatus, but a full development of it in Agaricus (Hebeloma) nauseosus. It becomes faint in Agaricus (Pholiota) heteroclitus, as it is also in Cortinarius nitrosus; but in all there is more or less of the same pungency, which recalls to mind the fumes of nitric acid. It may be inferred from the name of Hygrophorus nitratus that it possesses the same odour, and others might be named which partake of it in a less degree, so that this may be accepted as another type of odour to be found in many species of fungi. Here, again, the same question arises as to what value this peculiarity may be supposed to possess for the plant itself, because it is no symptom of decay, since it is present with the plants named above in their youngest and in their most healthy condition. Nothing that we have observed would suggest protection from, or attraction for, insects or mollusks.

Thus much for odours, which must be taken as suggestive, and not by any means exhaustive. The subject of taste may be passed over as of doubtful value in estimating attraction or repulsion, or at least it is of secondary importance, and should not stand in the way of a few suggestions on the subject of colour. It may be premised that, although such a large number of species of Agarics flourish amongst grass, very few possess a green colour.

We have alluded to one which is most commonly found amongst dead leaves; Russula virescens is seldom seen amongst grass, and the colour of Agaricus aeruginosus is not in the least concealed when growing amongst grass, until it has lost the greater part of its green gluten and exhibits the dirty yellow cuticle. Dull-coloured species, of various shades of olive, brown, and grey, are common enough, so as readily to be confounded with the soil, stones, and dead leaves, upon or amongst which they are growing; but what excuse can be made for the bright red and yellow species appearing in such gaudy attire? Reds verging upon deep orange, as in Agaricus (Amanita) muscarius, and passing through all stages of vermilion and carmine to deep purple, are by no means uncommon, especially in the genus Russula. And here it may be remarked that the species of Russula are to be seen in greatest plenty and perfection during those months when flowers are exhibiting their brightest colours, and before the mass of proper Agarics make an appearance. A red Russula in October or November would be a far more conspicuous object than if it occurred in June or July, when Russula puts in an appearance. Hygrophorus, on the other hand, is a late genus, containing some very bright red and yellow species; but these are small, and commonly so immersed in the grass, on lawns and pastures, that they are not conspicuous. Their "season” is October and November. It is easy enough to comprehend the advantage of coloration to such species as Hygrophorus psittacinus, Hygrophorus conicus, Hygrophorus Wynnie, and even of Hygrophorus chlorophanus, when seen growing amongst autumnal grass. The large species of Russula would, under the same conditions, be most conspicuous. Out of forty British species there are not less than twenty-five which are of some tint of red, or have varieties of those colours. What protective value can there be in expanded disks of bright scarlet 4 or 5 inches in diameter? If it should be contended that they are attractive, and not protective, then it becomes a question as to what they may attract. Slugs are fond enough of devouring not only red, but white and dull-coloured species, not refusing a meal upon one of the most poisonous (Russula emetica), and still it is the top of the pileus they devour, apparently in preference to the gills, so that they cannot be regarded as intelligent workers in the distribution of species.

A careful examination of the plates in any good illustrated work on the Agarics will show that in the whole of the old genus Agaricus, adding also Coprinus and Marasmius, the number of brightly coloured species are remarkably few. In the genus Cortinarius the colours are brighter, but they are not conspicuous when growing, because violet is not a demonstrative colour, and pale yellow, or lemon colour, is not observable amongst dead leaves. If space permitted it could be shown that, in a majority of instances, the colours of Agarics are protective, inasmuch as they harmonize remarkably with the matrix that supports them. With Russula, Lactarius, and Hygrophorus, the case is different, for there are many very obtrusive species, notably the red ones, for which we cannot formulate an excuse.

A word or two, in conclusion, on the intermediaries, or agencies, for the diffusion of fungi. It must be understood that in this communication we are confining ourselves to the large, or pileate, fungi, principally of the mushroom type. The agents named in the letter already alluded to are: "6 Horses, oxen, sheep, foxes, squirrels, moles, birds, snails, and insects." Squirrels are very fond of Boleti especially, but they eat the top of the pileus in preference to the pores, or spore-bearing surface; snails and slugs are undoubtedly mycophagous to a considerable extent. Of birds we have no evidence, as far as I am aware; ducks will eat fragments, when thrown to them, of such known virulence as Agaricus muscarius, and Boletus luridus without subsequent inconvenience, but

it is doubtful if birds seek fungi, except to beat them in pieces and pick out the larvæ. Whether horses, oxen, and sheep really eat the common mushroom, we venture to call in question, but they do eat the grass upon which fungus spores have fallen. We have observed horses, cattle, and sheep eating the grass all around where mushrooms have been growing, and seen them pass on, leaving the mushrooms for us to gather on our own account. This does not show much animal predilection for fungus food, and hardly bears out the paragraph that "horses, sheep, and oxen are all readily attracted by the taste and mealy smell" of the mushroom. Without venturing to throw doubt upon the old faith that the spores of the mushroom are doomed to pass through the entrails of a horse, or that a horse or cow may sometimes even eat a mushroom if one comes in its way, still we have great hesitation in accepting as an article of belief that horses are really so fond of fungi that they seek them out, and devour them bodily, for the sake of the preservation of the species. Mushroom gatherers by preference go into meadows and pastures where horses and cattle are feeding in order to fill their baskets, but this could hardly be the case if the animals themselves were so fond of the delicacy, and hence it may be inferred that it is not wholly true that mushroom spores pass through their host because that host recognizes the mealy smell and pleasant taste of the mushroom itself, but rather that they are swallowed unwittingly with the grass over which they are dispersed.

The general question still remains unanswered: "What can be the service which the presumably attractive characters of fungi induce animals to perform for them?" In the case of the Phalloidea there need be little hesitation in furnishing an answer. The foetid odour of Phallus, Clathrus, and their allies, undoubtedly attracts flies in great number, and these latter suck up the slimy mass, which contains the spores, with such avidity that scarce a speck is left. These spores are all most remarkably small, so as to leave no doubt as to their being ingested whole, and probably excreted in the same condition, but how, when, and where, is a mystery still. The inference would be that, if true in this instance, why not similarly in others? and hence the inquiry. Unfortunately the data are too few for generalization, and all we can do is to demonstrate that the subject is worthy of investigation, and, as Mr. Straton has observed, "one that requires the gathering together of much individual observation in all parts of the world." Few people hitherto have considered fungi of sufficient interest or importance for any other effort than to kick them over whenever encountered, but in this respect a reform would be imminent, if, by reiteration of the questions here set down, and a wider distribution of suggestions as to the kind of observations required, a larger number of persons could be interested in looking for and recording them. If there are no sexual elements to be discovered, it is still desirable to ascertain what conditions are requisite to secure the successful germination and growth of the agamospores, and how intervening agents might aid the process. The least glimmer of light is always welcome in a dark place.

LUMINOUS CLOUDS.

M. C. COOKE.

LUMINOUS clouds, which were first seen in 1885, are now acknowledged to have so much importance that it may be worth while to present a brief survey of the phenomenon and the facts established by the observation of it.

On June 23, 1885, about 9.50 p.m., local time, I noticed an extraordinary brilliance produced by lightclouds in the north-western sky. I had always previously I Not more than 3 micromillimetres in diameter.

directed great attention to clouds, and on this account these bright clouds appeared to me the more surprising and puzzling. About 9.50 p.m. the north-western and northern sky was covered, to the height of about 20°, with a layer of bright cirrus-like clouds, which reached from about N.W. to N.N.E. In this layer, the lowest part of which was concealed from me by houses and trees, three horizontal zones could be distinguished. The lower zone was without lustre, and had a yellowish appearance; higher up there was a strip, several degrees in breadth, which shone with an extremely beautiful, white-gleaming, silver-like light; above this strip was another like it, but not quite so brilliant, of a bluish tint. The light of the central zone was comparable to the light of the nearly full moon, when it stands at sunset at about 10°, more over the eastern horizon. About 10.30 p.m. the height of the upper limit of the phenomenon had been somewhat lowered; the three zones were still there, but had become especially the uppermost one-somewhat narrower. The position of my place of observation-Steglitz, near Berlin-is 52°5 N. lat.; about 9.50 p.m., local time, the depth of the sun below the horizon was about 9°. It is well known that, at this depth of the sun, ordinary clouds cannot any longer be affected by direct sunlight.

The same phenomenon appeared pretty often in the course of the following weeks; and I had, therefore, repeated opportunities of studying its peculiarities. I have never seen anything of the same kind at the time of sunset. As a rule, the phenomenon began to appear from 15 to 20 minutes-but sometimes 40 minutes, or more-after sunset. Several times I remarked that almost the whole sky-with the exception of a segment in S. E. at the height of from 10° to 20-was covered by the gradually increasing brilliance. In all these cases a gradual, progressive extinction of the phenomenon, proceeding from S.E. to N.W., was observed. The luminous clouds, when they first shone, generally gave forth only a feeble light. As the sun sank deeper, a gradual, but in the end complete, extinction of the phenomenon took place from the south-eastern side; but at the same time the light of the remaining part became steadily stronger, until it reached its highest degree of strength, when the upper limit in the N.W. had a height of about 12°. From that point onwards the strength of the light decreased.

On some evenings the phenomenon was specially striking, less in consequence of the light than in consequence of an occasional want of light. Several times I observed the sky having been perfectly clear when the sun set-that about an hour after sunset an absolutely impenetrable black wall, like a threatening thunder-cloud, appeared in the N.W., from the horizon to a height of from 5 to 20°. Higher up, on the contrary, the silverbright shining showed the presence of the phenomenon. Gradually the black shadow disappeared, from above downwards, and gave place to the intense shining.

Towards the end of the month of July 1885 the luminous clouds disappeared, and it seemed as if the phenomeno.. had come to an end. It was therefore the more surprising when, towards the end of May 1886, the phenomenon again presented itself suddenly. As in the preceding year, it remained visible, with some interruptions, until the beginning of August. The phenomenon has since been repeated from year to year, always at the same

season.

As the result of incessant efforts, I have succeeded in establishing that luminous clouds migrate in the atmosphere of the earth in such a way that during the months of December and January they are to be found in the southern hemisphere at the latitude of from about 48° to 60°. No information with regard to the phenomenon in equatorial regions has yet been received. This suggests the possibility that in passing through these regions it is not visible; but when we consider that also in the temperate zone there are extensive districts in which

the phenomenon must certainly have presented itself, but from which no record of observations has hitherto come, the fact that it has not yet been observed at the equator will not lead us to conclude that it is not visible there in intermediate times.

The above-mentioned decrease of the apparent height of the upper limit of the phenomenon, coinciding with the deeper sinking of the sun, causes us to recognize that it is due mainly to direct illumination by the sun. Starting from this assumption, we may readily find the principles for the determination of the height of the phenomenon. During the first years, therefore, I frequently made measurements of the apparent height of the loftiest point of the arc which limits the phenomenon towards the S. E.; and, having regard to the time of the measurements, I found that the distance of the phenomenon from the surface of the earth was from about 50 to 60 kilometres.

The knowledge of this extraordinary height excited in me the most intense interest, and my aim now was to determine the height by a more trustworthy method. For the ultimate success of my efforts I am especially indebted to the co-operation of Prof. Förster, Director of the Berlin Observatory. On the evening of July 6, 1887, Dr. Stolze and myself (the former having taken up his position in Berlin, while I observed the phenomenon from the Potsdam Observatory) succeeded in each getting two simultaneous photographs of the luminous clouds. The calculation made in accordance with these photographs gave a height of about 75 kilometres. But this estimate was not perfectly satisfactory, so far as precision was concerned; for, in the first place, the basis of about 26 kilometres was small; secondly, the direction of the basis was such that it formed with the direction towards the luminous clouds too small an angle; and, thirdly, the

photographic apparatus employed had not been worked with sufficient exactness.

In the year 1889 the luminous clouds were at last repeatedly and simultaneously photographed, with improved apparatus, at Steglitz and Nauen, which are distant from one another about 35 kilometres, and lie with regard to one another in the direction from east to west. At Rathenow also, 70 kilometres west from Steglitz, photographs were taken. These were not exactly simultaneous with the others, but the time differed only by a few seconds; and they are useful at least as a means of checking the results obtained from the photographs taken at Steglitz and Nauen.

From these photographs it is inferred with great certainty that the distance of the luminous clouds from the surface of the earth on July 2, 1889, was 81 kilometres, and that it was 82 kilometres on July 31, 1889. For June 12 there is an estimate of 90 kilometres, but this is less certain than the other two.

These results follow from the measurement of 108 different points, corresponding to one another, which are distributed on six pairs of plates; and it is interesting, from the remaining errors of the single groups, to test more closely the question what part is taken in these errors by, say, the thickness of the cloud-layer in a vertical direction.

It is well known that there is a certain law relating to the probability of the distribution of errors in accordance with their greatness. According to this law, it is to be anticipated that errors which lie between the triple and the quadruple value of the mean error, occur once among 80 different points which have been measured in the photographs of July 2 (in which the conditions of accuracy were the most favourable); and, further, that of errors which lie between the double and the triple value of the mean error six are to be expected. In reality, the calculations agreed very well with the number of observed cases-viz. 2 and 5 respectively.

These figures show very plainly that the differences of the results with regard to the height are essentially a consequence of errors of measurement, and that the thickness of the cloud-layer itself was very small, perhaps only the fraction of a kilometre. With this agrees the almost exactly similar aspect of the phenomenon at the two places of observation.

Figs. 1 and 2 represent the phenomenon as it appeared on July 2, 1889. The photograph reproduced in Fig. 1 was taken in Steglitz at 13h. 21m. os., Berlin mean time, and Fig. 2 simultaneously at Nauen. It is interesting to observe the parallactic shifting of the same cloud-points, in the two illustrations, in a fixed direction. In each of the illustrations, two stars, a and ẞ Auriga, appear. On account of the enormous distance, the lines of direction, in which one and the same star is seen simultaneously from different points of view, are parallel to one another.

Hence the deviation of two corresponding cloud-points, in the illustrations, with regard to one and the same star, gives a measure for the parallax of those cloud-points, on the supposition that the focal distance of the photographic apparatus is known. The focal distance of the two sets of apparatus was precisely determined by the photographing of stars, and proved to be almost exactly 200 mm. In accordance with this the above-mentioned height of 81 kilometres was found.

The following peculiarities, which observation of luminous clouds has firmly established, are of great interest :

(1) Luminous clouds had in general a very rapid movement from north-east to south-west. In some cases movements also took place in the opposite direction; but these were always much slower-and they were also much less frequent-than those first named.

LORD RAYLEIGH has been appointed an honorary member of the Bavarian Royal Academy of Science.

PROF. J. A. EWING, F.R. S., has been elected Professor of Mechanism and Applied Mathematics at Cambridge, in succession to Prof. Stuart.

MR. WILLIAM LEADBETTER CALDERWOOD, who was for several years naturalist to the Fishery Board for Scotland, has been appointed Director of the Laboratory for Marine Zoology at Plymouth.

SOME time ago the Phi Beta Kappa Society proposed that the four hundredth anniversary of the discovery of America should be signalized by a memorial history of American literature and science. Two prizes of 3000 dollars each were to be offered for the best general survey of American literature and science respectively; and, in addition to this, it was proposed that the preparation of an extensive and detailed account of scientific achievement should be prepared, the work for each department being entrusted to a specialist in that department. The New York Nation, which calls attention to the matter, speaks of this last undertaking as "the really serious task, and the only part of the scheme which possessed in a high degree the monumental character." We learn from the Nation that a committee having the project in charge is about to meet and confer upon the initiation of the work. The committee consists of the presidents of six of the most important American Universities, together with one or two other gentlemen of equal eminence.

IN the Kew Bulletin for November many interesting facts with regard to the cultivation of Liberian coffee are brought together. The same number contains an excellent account of the cola nut (Cola acuminata, R. Br.). In early times, cola nuts were supposed to be used merely as a means for rendering water sweet and palatable when drunk before or after meals. "But," says the Bulletin, "it was soon evident that they possessed other properties, and that they had been selected as if by intuition on account of the property which undoubtedly they did possess of supplying a necessary stimulus to those who have to endure an occasional or prolonged deficiency of animal food; for in West Africa, as in other parts of the tropics, the flesh of animals is often scarce and difficult to procure. The use of cola nuts to render water palatable may be compared to that of olives in European countries. The latter are well known to enhance the flavour of whatever is eaten after them. On the other hand, the power said to be possessed by cola nuts of staying the cravings of hunger, and of enabling those who eat them to endure prolonged labour without fatigue, is comparable to that ascribed to the leaves of the coca plant of Ecuador and Peru. In fact, cola nuts in Western Africa play the same part that Erythroxylon Coca does in South America."

ON Monday, the Master (Sir James Whitehead), the Wardens and Court of the Fruiterers' Company, and others, had an interview with the Lord Mayor at the Mansion House, to seek his aid in a project for the encouragement of the culture of British fruit. Sir James Whitehead, addressing the Lord Mayor, said that, having regard to the great success which had attended the recent exhibition of fruit at Guildhall, the Fruiterers' Company were now proposing to increase their operations in the same direction. Their idea was to have fruit shows in different parts of the country, similar to the annual shows of the Royal Agricultural Society of England, in co-operation with the local horticultural societies. During these shows there would be lectures on various subjects connected with the cultivation of fruit. It would be the aim of the Company to give the warmest encouragement to the various horticultural societies, and to stir up a spirit of emulation among the local and parochial organizations. The Company had arranged that the committee of ex

perts who recently assisted them in connection with the Guildhall exhibition should meet once a month, and receive and answer questions on the subject of fruit culture. It was estimated that to carry out these objects a fund of about £20,000 would be necessary. It was believed that landed proprietors and the City Companies would be willing to aid this effort, and they might even obtain the assistance of a Government grant. What they asked the Lord Mayor to do was, first, to allow a great public meeting to be held at the Mansion House, and, secondly, to organize a Mansion House fund with the view of raising the necessary sum. The Lord Mayor cordially agreed to convene and preside over such a meeting as was suggested, but reserved his decision as to the raising of a Mansion House fund.

MR. SHIRLEY HIBBERD, the well-known horticulturist, died at his residence at Kew on Sunday. He was for many years editor of the Gardener's Magazine, and was the author of many works on horticulture. Mr. Hibberd was in his sixty-sixth year.

ON Saturday evening several shocks of earthquake were felt in the north-east of Scotland. The Daily News says that the first shock was experienced at 5.50 p.m. in Inverness, and that it lasted about 30 seconds. A good deal of damage was done to property by the falling of gables, chimneys, &c. The inhabitants were very much excited. Half an hour afterwards a second shock was experienced, but was not of so severe a character. About 6 o'clock a sharp shock of earthquake was felt at Forres. The disturbance was accompanied by a rumbling noise, with heaving and convulsion, which lasted from 15 to 20 seconds. It was felt over a radius of several miles. The Times says the earthquake was felt at Beauly, Inverness-shire, where many shops and houses were severely shaken, and furniture was thrown down. In Western Lovat a chimney-stack was knocked over. We learn from a correspondent at Nairn that "a slight vibration" was felt there and in the surrounding district "about 6 p.m."

AT the fourth annual general meeting of the Anthropological President, Mr. Denzil Ibbetson. Society of Bombay, an address was delivered by the retiring Speaking of the valuable contributions that might be made to anthropology by native inquirers, Mr. Ibbetson pointed out that sources of information are freely opened to them to which Englishmen can gain access only with difficulty. "It is through their agency alone," he said, "that we can hope to learn the rites and customs particular to women, rites and customs which I believe to possess a very special significance, as being in many cases handed down directly from the aboriginal women of the country, with whom the subsequent immigrants intermarried. And their facilities of communication with the masses are so infinitely greater than our own, that I look forward to the most valuable results so soon as we have a body of native gentlemen intelligently studying the anthropology of India. At present, in Upper India at any rate, a native who is sufficiently educated to understand the nature and object of our inquiries is too often hampered by his religious education, which causes him to describe the religion of the peasantry as it should be rather than as it is, and by his pride of caste, which prevents him from interesting himself in those whom he considers beneath his notice."

A PASSAGE in an appendix to Mr. Scott's last report on the administration of the Northern Shan States shows the extraordinary mixture of peoples and tongues in this region, and shows also what a task there is for the ethnologist of the future to unravel the tangled skein presented to him by the Shan State of Mainglin. The report says the population consists of Shans, Las, Was, Kachins, Shan-Taloks, Myen, and a tribe known as Mutso. The Las men dress like Shans, but their clothes are of black or