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400 ground and grows rapidly. The thickets become so dense that it is impossible to travel through them. In time only the fittest survive, and there remains a thrifty, vigorous stand of this valuable timber." In Montana the lodge-pole pine usually takes possession of burnt areas; but I saw near Belton on the Great Northern Railway a hillside which had been swept by a fire, leaving a good number of larch trees unharmed, all the trees of other species being destroyed, and larch seedlings were coming up in profusion. On the Stillwater Creek farther west I noticed a burnt area on which the lodge-pole pines were about 30 feet high; and amongst them larch seedlings were growing in openings exposed to sunlight during at least a part of the day. Here in time the lodge-pole pine will be supplanted by the larch. Sargent's statement, that young seedlings of the western larch are able to grow up under the shade of other trees, which they finally overtop and subdue, requires modification. Seedlings never occur in the shade of the forest, and are most numerous in open places exposed to full sunlight; but on good soil, as on a recently burnt area, they will spring up in the partial shade of small pine trees. The western larch is not a fast grower in the young stage; at Belton seedlings twelve years old, growing on rather poor rocky ground, were from 7 to 12 feet high.

As the seed of the western larch had never been collected, so far as we knew, by any one except Mr. Carl Purdy's collector in 1903, I visited Montana in 1906, with the object of collecting a large quantity for Sir John Stirling Maxwell and Lord Kesteven. In the common larch the seeds do not fall out of the cones until spring, and their collection during winter is an easy matter. The western larch behaves very differently, as will be seen by the following notes of my observations in Montana. About the middle of August the squirrels begin to throw down cones, a sign that the seeds are nearly ripe. About the 10th September the leaves, which form a tuft at the base of the cone, begin to turn yellow, and in a day or two become brown and withered, showing that the supply of nutrition to the cone is stopped. The cones, which until now were purplish in colour, become brown, and the scales gape open widely, allowing the seeds to escape. By the 20th September all the cones on the trees have become quite brown, and have emptied all their seeds. The empty cones remain on the branches till the autumn of the following year, by which time their peduncles have rotted and the cones are ready to fall. For collecting seed the larch forests must be visited during the first three weeks of September; and localities where felling is being carried on should be chosen, as the cones occur only at the summit of very tall trees, which are troublesome to cut down, even if permission to do so has been obtained from their owners. The western larch appears to produce a good crop of seed once every two or three years, and this is general over the whole region. 1906 was a remarkably poor year, scarcely any cones having been formed. In 1905, judging from the old cones of that year still remaining on the trees, the crop of seed was very abundant.

As I had long been trying to find a larch that would in England be less liable to the attacks of Peziza Willkommii than the common larch, I made inquiries as