CHAP. CXIII.

CONl'FERlE. iA'RIX.

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planted upon dry soil, were attacked by a small insect, resembling the wire-worm, from | in. to fin. in length. From 10 to 20 worms, and sometimesmore, have been observed at the root of one tree. (Tram t. Soc. Arts, vol.xxxviii. p. 6.)

Fungi. The European larch, and also the Russian variety, when old, or whenthe trunk is beginning to decay, will produce the Foletus laricis, which is calledby some authors -dgaricus pungens, and which is used in Russia, and someother parts of the north of Europe, as an emetic in intermittent fevers. It isalso the agaric of the larch of the shops. The body of this fungus is sapona-ceous ; and, Pallas informs us, is used by the women in some parts of Siberiato wash themselves and their linen. The Tungouses dye the hair of theirreindeer with it and the roots of Galium verum, of a deep red colour. Forother .Fungi growing on the larch, see the general article on the Fungi of the^bietinae, p. 2146.

The Rot in Larch Wood is a disease which has hitherto baffled every attemptof physiologists and planters to ascertain its cause. It seems to have beenfirst observed about the beginning of the present century, when some larchtrees growing in fertile soils were cut down and sawn up for use. We arenot aware of any record of the disease earlier than that given in our Treatiseon Country Residences, published in 1806. In Sang’s Planter's Kalendar, thefirst edition of which was published in 1812, several instances are given ofthe rot having appeared in Fifeshire, apparently from the trees having beenplanted in too rich a soil, and too warm a situation. Pontey does not noticethe rot in larch, though he does that of timber trees in general; but Matthewtreats of it at some length. In the Gardener's Magazine, the subject is dis-cussed by Mr. Gorrie anil Mr. Munro; and there are several articles on thesubject in the Quarterly Journal of Agriculture ; one of which, written in an-swer to certain questions put by the editor of that journal to Professor DeCandolle of Geneva, we have already quoted from. From all these sources,and some other incidental ones, we are only able to give the following un-satisfactory account: —

The rot attacks trees at various ages, and in different soils and situations.There are instances, in Scotland, of larch trees of 8 or 10 years’ growth havingthe interior of their stems tainted with the rot ; but, in general, both in Eng-land and Scotland, it does not attack the trees till they are from 20 to 30years of age. It generally commences at the root, and proceeds upwards,rotting the heart of the trunk ; but, in some instances, it has been found tocommence at the top of the tree, and proceed downwards. In a majority ofcases, Matthew observes, the rot commences in the roots which have struckdown deepest into the earth ; especially those immediately under the trunkof the tree. Thence, the corruption proceeds upwards in the centre of thetrunk ; which, when much diseased, swells considerably for a few feet abovethe ground ; evidently, Mr. Matthew observes, from the new layers of sap woodforming thicker there, to afford necessary space for the fluid to pass upwardsand downwards; the matured wood, through which there is no circulation,approaching, at the lower part of the trunk, to within one or two annuallayers of the bark. The disease can scarcely be detected by the externalappearance of the tree ; but, when it is cut down, the interior of the trunk isfound browm and rotten to a greater or less extent; and, in trees which havebeen subject to the disease for some years, the centre is so entirely rotten asto have become hollow, like a pipe or wooden pump ; and hence, as beforeobserved, the name of pumping has been applied to this disease. Sections oftrees, of different ages and sizes, affected in this manner, have been sent to usby r Mr. Gorrie and Mr. Munro. (See Gard. Mag., vol. ix. p.551.; and vol. x.p. 554.) Fig. 2266. a shows a section of a larger-sized tree, in which the pump-ing has only just commenced, though the rot has extended itself so as to dis-colour the whole of the heart wood ; and fig. 2266. b a section of a young treein which pumping has begun early, and extended very considerably, in pro-portion to the diameter of the trunk. In some soils, the rot commences as

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