=Remedy.=—Several remedies have been more or less successfully tried with a view to getting rid of the disease on trees, such as by cutting and scraping out the injured portions, and applying a suitable dressing; but such remedies, although suited for single specimens, cannot be applied to a whole area of infested trees. Under exceptionally favourable conditions, I have found the larch to outgrow the disease, though the cankered, swollen stems are never afterwards of great value for constructive purposes. Prevention in the present case is undoubtedly the best measure, for when once it has made headway, the larch disease is most difficult to cope with. By planting only sound, healthy trees, with uninjured roots in the most suitable soils and situations, and retaining these in as healthy a condition as possible, can we guard against attacks of the disease. Hardwoods mixed with the larch are to be recommended. _Polyporus squamosus_ attacks the elm and other hard-wooded trees and rapidly brings about decay. It is one of our commonest species on diseased trees. The =Sycamore Fungus= (_Rhytisma acerinum_).—Every one interested in trees must be familiar with the conspicuous black, pitch-like spots which so mar the appearance of sycamore leaves. These are due to the above-named fungus which, appearing as small yellowish spots on the undersides of the leaves towards the end of June, gradually increase in size and intensity of colour until they attain to fully half an inch in diameter and are inky black, with a margin of dirty yellow. The attacked portion of the leaf becomes wrinkled and much thickened in texture, while all the affected foliage drops off prematurely. After lying on the ground during the winter, the thread-like spores are produced in large quantities at the time when the foliage of the sycamore is appearing in May and June. The sycamore is not the only tree affected by this fungus, for the Norway Maple and our native _Acer campestre_ are equally liable to attack, and have in some instances suffered very severely from this cause. The fungus is becoming more plentiful, and it disfigures the maple and sycamore leaves to a wide extent. [Illustration: POLYPORUS SQUAMOSUS (ON ELM TREE)] _Rhytisma punctata_ may at once be distinguished from the above species by the many small black spots studded thickly together, which combine to form the large conspicuous blotches for which affected trees are remarkable. Both species are sometimes found on the same leaf. As the attacks of this fungus continue from year to year, and cause almost every leaf to drop off prematurely, the health of the trees is greatly impaired, and they become an easy prey to the still more destructive coral spot fungus, _Nectria cinnabarina_. By burning the leaves affected with _Rhytisma_ before the spores are liberated in spring, the spread of the fungus is prevented in a simple and effective manner. The sycamore fungus is very plentiful on trees around London.