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just render the morphological resemblance, if it exists, the more cu- 

 rious and striking. It should be noticed that this resemblance can 

 be observed only when both the stems and the veins are fully and 

 fairly developed, 



" In prosecuting this inquiry, let us first inspect, in a general way, 

 the leaf of a tree, with its central vein or veins, and its side veins. 

 Even on the most careless inspection, the central vein will be found 

 to bear a striking analogy to the central stem or axis of the tree, and 

 the side veins to the branches. Having viewed the leaf in the first 

 instance, let us then look at the tree when stripped of its leaves in 

 winter, and we shall see how like it is in its contour and skeleton to 

 the contour and skeleton of a leaf. We shall be particularly struck 

 with this if we view it in the dim twilight or the 'pale moonlight' 

 between us and a clear sky. In both leaf and tree we see a central 

 stem or stems with ramified appendages going off at certain angles ; 

 and we may observe that the tree in its outline tends to assume the 

 form of a leaf. 



" The general impression produced by a first glance will be con- 

 firmed on further inspection. The analogy between the skeleton of 

 the leaf and the skeleton of the branch may be seen in a number of 

 points, as well as in the general resemblance between the ramification 

 of the plant and the ramification of the venation of the leaf. 1st. 

 Some trees, such as the beech, the elm, the oak, the holly, the Portu- 

 gal and bay laurels, the privet, the box, will be found to send out 

 side branches along the axis from the root, or near the very root, and 

 the leaves of those trees have little or no petiole or leaf-stalk, but 

 begin to expand from nearly the very place where the leaf springs 

 from the stem. There are other trees, as the common sycamore (the 

 Scotch plane-tree), the beech, the chestnut, the pear, the cherry, the 

 apple, which have a considerably long unbranched trunk, and the 

 leaves of these trees will be found to have a pretty long leaf-stalk. 

 2nd. Most of our low, branching, herbaceous plants, such as the mal- 

 lows, rhubarb, Tussilago, marsh marigold, lady's mantle, hollyhocks, 

 send out a considerable number of stems from near the root, and it 

 will be found in exact accordance with this, that these set off from 

 the base of the leaf a considerable number of main veins or ribs, 

 which as they spread cause the leaf to assume a rounded shape. In 

 these plants, the morphological resemblance between tree and plant 

 is seen horizontally, and not vertically. In this respect these plants 

 are different from our forest trees, which send up commonly one main 

 axis with lateral branches, and have in their venation one leading 



