BOTANY. 



35 



sized tree, the largest having an altitude of 50 or 60 feet, and a diameter of trunk of 12 inches 

 three feet from the ground. The form of the tree is erect and strict ; the foliage yellow green, 

 moderately dense ; leaves in twos, two inches long, and covering all the smaller branches ; the 

 cones H inches long, narrow ovoid ; scales bearing short sharp spires, which are obsolete at the 

 base of the cone. The old cones are persistent, sometimes loading the branches and giving a 

 peculiar appearance to the tree. On Klamath river are many scattered trees having the same 

 character and station as those on Canoe creek, but by far the greater number are gathered into 

 the low grounds near the stream, where they form dense thickets or pine swamps of trees, gen- 

 erally 25 to 40 feet high and 6 to 10 inches diameter, so closely set as seriously to obstruct our 

 passage through them. 



Fig. 11. 



Fig. 11. Cone, leaves, scales, and seeds of P. coniorla, natural size. 



On the lowlands bordering the western shore of Upper Klamath lake, this pine exclusively 

 composes the forest which formed the wall-like limit of the level and grass covered prairies 

 which spread many miles back from the water's edge, the highland more remote being covered 

 with the much larger trees of P. ponderosa. 



The pumice plain lying between the Klamath lakes and the Des Chutes river, the driest and 

 most barren region which we crossed, is sparsely covered with the western cedar (J. occidentalis) 

 and P. contorta, here lower and more spreading, its lower branches resting on the ground. Of 

 these trees many were dead, though standing, and all then exhibited very strikingly a character 

 which may have suggested the name "contorta" to Douglas, but which is common to many 

 conifers, though perhaps nowhere so conspicuous as in this tree, viz : the curving downward 

 and inward of the dead branches, reversing the natural upward curve of their extremities while 

 living. 



