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Roses have to contend against the two forms of Phragmidium mucronatum as well as Asteroma Rosa. Still more disastrous is a species of Erysiphei, which at first appears like a dense white mould. This is named Sphærotheca pannosa. Nor is this all, for Peronospora sparsa, when it attacks roses in conservatories, is merciless in its exactions.* Sometimes violets will be distorted and spoiled by Urocystis Viola. The garden anemone is freely attacked by Ecidium quadrifidum. Orchids are liable to spot from fungi on the leaves, and recently the whole of the choicest hollyhocks have been threatened with destruction by a merciless foe in Puccinia malvacearum. This fungus was first made known to the world as an inhabitant of South America many years ago. It seems next to have come into notoriety in the Australian colonies. Then two or three years ago we hear of it for the first time on the continent of Europe, and last year for the first time in any threatening form in our own islands. During the present year its ravages are spreading, until all admirers of hollyhocks begin to feel alarm lest it should entirely exterminate the hollyhock from cultivation. It is common on wild mallows, and cotton cultivators must be on the alert, for there is a probability that other malvaceous plants may suffer.

A writer in the "Gardener's Chronicle " has proposed a remedy for the hollyhock disease, which he hopes will prove effectual. He says, "This terrible disease has now, for twelve months, threatened the complete annihilation of the glorious family of hollyhock, and to baffle all the antidotes that the ingenuity of man could suggest, so rapidly does it spread and accomplish its deadly work. Of this I have had very sad evidence, as last year at this time I had charge of, if not the largest, one of the largest and finest collections of hollyhocks anywhere in cultivation, which had been under my special care for eleven years, and up to within a month of my resigning that position I had observed nothing uncommon amongst them; but before taking my final leave of them I had to witness the melancholy spectacle of bed after bed being smitten down, and amongst them many splendid seedlings, which had cost me years of patience and

* Berkeley, in "Gardener's Chronicle," 1862, p. 308.

anxiety to produce. And again, upon taking a share and the management of this business, another infected collection fell to my lot, so that I have been doing earnest battle with this disease since its first appearance amongst us, and I must confess that, up to a very short time back, I had come in for a great deal the worst of the fight, although I had made use of every agent I could imagine as being likely to aid me, and all that many competent friends could suggest. But lately I was reminded of Condy's patent fluid, diluted with water, and at once procured a bottle of the green quality, and applied it in the proportion of a large tablespoonful to one quart of water, and upon examining the plants dressed, twelve hours afterwards, was delighted to find it had effectually destroyed the disease (which is easily discernible, as when it is living and thriving it is of a light grey colour, but when killed it becomes of a rusty black). Further to test the power at which the plant was capable of bearing the antidote without injury, I used it double the strength. This dose was instant death to the pest, leaving no trace of any injury to the foliage. As to its application, I advocate sponging in all dressings of this description. Syringing is a very ready means, but very wasteful. No doubt sponging consumes more time, but taking into consideration the more effectual manner in which the dressing can be executed alone, it is in the end most economical, especially in regard to this little parasite. I have found it difficult by syringing, as it has great power of resisting and throwing off moisture, and if but a very few are left living, it is astonishing how quickly it redistributes itself. I feel confident, that by the application of this remedy in time another season, I shall keep this collection clean. I believe planting the hollyhock in large crowded beds should be avoided, as I have observed the closer they are growing the more virulently does the disease attack them, whereas isolated rows and plants are but little injured.'

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The "Gardener's Chronicle" has also sounded a note of warning that a species of Uredine has been very destructive to pelargoniums at the Cape of Good Hope. Hitherto these plants

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have not suffered much in this country from parasites. Besides these, there are many other less troublesome parasites, such as Uredo filicum, on ferns; Puccinia Lychnidearum, on leaves of sweet-william; Uredo Orchidis, on leaves of orchids, &c.

If we would sum up the influences of fungi in a few words, it could be done somewhat in the following form. Fungi exert a deleterious influence

On Man,

When eaten inadvertently.

By the destruction of his legitimate food.
In producing or aggravating skin diseases.

On Animals,

By deteriorating or diminishing their food supplies.
By establishing themselves as parasites on some species.

On Plants,

By hastening the decay of timber.

By establishing themselves as parasites.
By impregnating the soil.

But it is not proved that they produce epidemic diseases in man or animals, or that the dissemination of their multitudinous spores in the atmosphere has any appreciable influence on the health of the human race. Hence their association with cholera, diarrhoea, measles, scarlatina, and the manifold ills that flesh is heir to, as producing or aggravating causes, must, in the present state of our knowledge and experience, be deemed apocryphal.

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HABITATS.

Ir commonly happens that one of the first inquiries which the student seeks to have answered, after an interest is excited in fungi, is—Where, an:1 under what circumstances, are they to be found? The inexperienced, indeed, require some guide, or much labour will be expended and patience lost in seeking microscopic forms in just such places as they are least likely to inhabit. Nor is it wholly unprofitable or uninteresting for others, who do not claim to be students, to summarize the habitats of these organisms, and learn how much the circumstances of their immediate surrounding elements influence production. For reasons which will at once be recognized by the mycologist, the most satisfactory method of study will be somewhat that of the natural groups into which fungi are divided.

AGARICINI.—There is such a close affinity between all the genera of this group that it will be a manifest advantage to take together all those fleshy pileate fungi, the fruit of which is borne on folded plates or gills. It must be premised of this group that, for the majority, shade, a moderate amount of moisture, and steady warmth, but not too great heat, are required. A stroll through a wood in autumn will afford good evidence of the predilection of Agaricini, as well as some smaller groups, for such spots. A larger proportion will be found in woods, where shade is afforded, than on open heaths or pastures. These wood-loving forms will consist, again, of those which appear on the soil, and those which are found on rotten stumps and decaying trees. Many of those which grow on trees have a

lateral stem, or scarcely any stem at all. It may be remarked, that some species which spring from the soil delight most in the shelter of particular trees. The Agarics of a beech wood will materially differ largely from those in an oak wood, and both will differ from those which spring up beneath coniferous trees.

It may be accepted as true of the largest proportion of terrestrial species, that if they do not spring directly from rotten leaves, and vegetable débris in the last stage of decay, the soil will be rich in vegetable humus. A few only occur on sandy spots. The genus Marasmius is much addicted to dead leaves; Russula, to open places in woods, springing immediately from the soil. Lactarius prefers trees, and when found in exposed situations, occurs mostly under the shadow of trees.* Cantharellus, again, is a woodland genus, many of the species loving to grow amongst grass or moss, and some as parasites on the latter. Coprinus is not a genus much addicted to woods, but is rather peculiar in its attachment to man-if such expression, or one even implying domesticity, might be employed-farmyards, gardens, dunghills, the base of old gateposts and railings, in cellars, on plaster walls, and even on old damp carpets. Hygrophorus loves "the open," whether pastures, lawns, heaths, commons, or up the slopes of mountains, nearly to the top of the highest found in Great Britain. Cortinarius seems to have a preference for woods, whilst Bolbitius affects dung, or a rich soil. Lentinus, Panus, Lenzites, and Schizophyllum all grow on wood. Coming to the subgenera of Agaricus, we find Pleurotus, Crepidotus, Pluteus, Collybia, Pholiota, Flammula, Hypholoma, and some species of Psathyra growing on wood, old stumps, or charcoal; Amanita, Tricholoma, and Hebeloma most attached to woods; Clitocybe and Mycena chiefly amongst leaves; Nolanea amongst grass; Omphalia and Galera chiefly in swampy places; Lepiota, Leptonia, Psalliota, Stropharia, Psilocybe, and Psathyrella mostly in open places and pastures; Deconica and Panaeolus mostly on dung; Entoloma and Clitopilus chiefly terrestrial, and the rest variable.

*These predilections must be accepted as general, to which there will be exceptions.

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