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MICRO-FUNGI: WHEN AND WHERE TO FIND THEM |
AUGUSTCERTAIN members of the interesting group of micro-fungi, known as Pucciniaei, have had our attention in previous papers as they have been gradually coming to the front. Now we have them in great plenty. The straw stalks of wheat and the leaves of wheat, as also certain grasses, are frequently infested with a member of the group known as Puccinia graminis, the spores of which, like those of other Puccinia proper, are two celled, but they are larger and much longer than most if not all other members of the group, and possess a lengthened stalk or peduncle. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 4 Fig. 57-59 Garden mint is now likely to develop a Puccinia, for I have found it yearly during some eight or ten years about this time in a neighbour's garden, on the outskirts of Manchester and elsewhere. This smut Puccinia menthae is also found on wild mint and other plants, but it is more rare on the wild than the garden mint. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 4 Fig. 69-70 P. glomerata is to be found on the ragwort now, and will continue with us almost to the end of the year. It must, I think, be very common, for I have met with it so frequently round about Manchester as also far away from that city. The species of ragwort, Senecio jacobaea, on which I have usnally found the smut, is one of our most common wild plants. Puccinia variabilis, which infests that common weed the dandelion, claims our special attention from the circumstance of the strange variations which exist in the forms of its spores. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 4 Fig. 82-83 Some are rounded, others stunted or variously elongated, while occasionally they are formed of three cells, whereas the common characteristic of Puccinia is that they are two celled. It is but seldom that I have met with this singular variation of three cells from the normal condition of the spores. In some portions of the country the fungus is very common, and I have found almost every leaf infested, in others it is very rare, if ever met with. This is the case in Lancashire and Cheshire so far as my experience goes. Belonging the Pucciniaei there are several species of another group of leaf-fungi which have a special claim upon our attention. I allude to those known as Phragmidiums. They may all be met with about this time, but some in favourable localities will have appeared earlier, while others will linger on even a month or two longer. Instead of being two celled like the Puccinia, they are made up of three, four, five, or in some instances six cells, thus forming a small string of cells. Upon the leaves of plants where they grow they assume an aggregated appearance and form tufts, and well dried and mounted in this condition as opaque objects make most charming slides for the microscope. The whole of the group have peduncles or stalks of attachment to the leaves upon which they grow, and as they are not. numerous I will refer to the whole of the known British species. The most conspicuous of the group is the bramble brand, Phragmidium bulbosum, and it is very common over a large extent of country,especially in Wales and the Lake District. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 3 Fig. 41 In other localities I have met with it - as for example - in Cheshire and Derbyshire, but in these cases always in smaller quantity. The P. bulbosum I have found as late as October on one occasion, as also I, on the same occasion, met with raspberry brand - Phragmidium gracile. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 3 Fig. 43 In those two instances the plants were in fair condition, although the season was so far gone. The raspberry brand is a smaller fungus than the bramble brand, and the reader will find the distinction most marked, besides the leaves of the two plants at once determine the question. The leaf of the bramble is prickly and of a coarser structure than the leaf of the raspberry. The Rose brand, Phragmidium mucronatum, is not so common as the two other brands I have already named, but still it cannot be called scarce, for in favourable localities it is plentiful. In the open country at the proper time it may be found by the student upon the leaves of the common dog rose. The best find I ever made of this Phragmidium was near Southport some ten years ago about this time. I have met with it frequently elsewhere, but never upon the cultivated or garden rose. The Strawberry brand, Phragmidium obtusatum, ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 3 Fig. 35 and the Burnet brand, Phragmidium acuminatum, ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 3 Fig. 32 are both somewhat smaller fungi than those previously named. The first is found on the leaves of the wild strawberry plant. I have met with it on two occasions in moderate quantity, but I am inclined to think it rare. One occasion was when I was at Aberystwyth, and the other within about a mile of the sea coast in the Lake District. The P. acuminatum is a still rarer fungus, and when found upon the leaf of the burnet is generally in small quantity, and very likely to be overlooked by the student. It is in a case of this kind that a good pocket lens is extremely useful. We have another member of this group named by Dr. Cooke, Phragmidium bullatum. This fungus is said to grow upon the twigs of the dog rose, but as yet I have not had the good fortune to meet with it. I have just spoken of Phragmidium acuminatum as growing upon the burnet. It should however be remembered that it is the smaller burnet, Poterium sanguisorba, upon which the fungus grows, for we have a larger burnet, Sanguisorba officinalis, and this also furnishes us with an interesting brand - I allude to the charming chain brand, Xenodochus carbonarius. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 3 Fig. 29 This is one of the most pleasing and interesting of all the leaf-fungi, and is said by Dr. Cooke to be very rare. Notwithstanding this opinion of the Doctor, I have to say for the encouragement of the reader that I find it every summer in plenty. My chief gatherings have been in the Buxton valley some two or three miles from the town. I can any summer find it also in Cheshire in the valley of the Bollin in fields near the river. I have received it from Montgomeryshire, and I doubt not it may be found in numerous localities. The brand has the general characteristics of a Phragmidium, but it is greatly extended in length, and forms a beautiful chain as of beads, a sort of fairy necklace. Besides this there is still a smaller chain brand, I allude to Xenodochus curtus, which has never been found but once when the writer had the good fortune to meet with it in September, 1873. Specimens of the fungus were forwarded to Dr. Cooke, and he has in the later editions of his work, "Rust, Smut, Mildew, and Mould", given a full description of the plant to which I beg to refer the reader. The plant upon which it was found is Valeriana officinalis, and it will give me pleasure if I can hear of other students meeting with this very rare fungus. For the information of the reader, I will explain the locality in which I met with it. On the high road from Buxton to Bakewell there is the village of Taddington, about equal distance betwixt the two places. Going in the direction of Bakewell from Taddington and about a mile from the village is a wood on the left hand or eastern side of the road. It was in this wood and not many yards from the road that I found Xenodochus curtus. I have made many efforts since my discovery to find more of the fungus, but I regret to say always without success. The reader will find August a favourable month for gathering another curious group of leaf-fungi, known as Erysiphe. The general structure and physiology of these fungi differ greatly from all others that have claimed our attention. Their appearance as seen on the leaves of the plants upon which they grow is that of small cannon balls, and they are most difficult to find on account of their extreme minuteness. The one on the burdock - burdock blight, Erysiphe montagnei, is, I think, the best to find on account of the large quantity and comparative largeness of the fungus. Whenever the reader meets with the leaves of the burdock in a decayed condition, he will most probably find such leaves infested with the fungus in an unmistakable manner. The mugwort is infested with a much smaller fungus, Erysphe Linkii. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 12 Fig. 248-249 This I have found in numerous localities in Lancashire and Cheshire, and I have reason to look upon it as common. We have one member of this group on peas and beans and various other plants. It is known as Erysiphe Martii, and is very common in autumn. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 11 Fig. 237-239 Besides those I have already named we have Grass Blight, Erysiphe graminis; ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 11 Fig. 235-236 we have the Composite Blight, Erysiphe lamprocarpa, on plantain, and sundry other plants; ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 12 Fig. 250-251 we have the Buttercup Blight, Erysiphe communis, ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 11 Fig. 240-242 and the Bugloss Blight, Erysiphe horridula, and lastly Cornel Blight, Erysiphe tortilis. ![]() Rust, Smut, Mildew & Mould - M.C.Cooke - Plate 12 Fig. 245-246 The last, which is to be found upon the leaves of the dogwood, Cornus sanguinea, I have met with but once. Still I don't think it scarce, but its extreme minuteness makes it difficult to find. One peculiarity of this group of fungi is that they are surrounded with singular radiating appendages, an idea of the general characteristics of which may be gathered from the figure VI on Plate No. 1. Another is that the spores of the fungus are developed in a sort of pod called an ascus, each ascus containing two spores [VIa Plate 1]. If the student desires to see the spores in ascus he should take one or more of the parasites from the leaf, place them in water and burst them by pressure when under the microscope, when he cannot well fail to find what he is looking for, as also the remarkable appendages connected with the parasite. |