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now, you pass two very good specimens of the great- 

 leaved magnolia. You can tell them at once by their 

 very large (often three feet long) leaves, crowded close 

 at the ends of the branches. In shape they are ob- 

 long, and narrow gradually down from a broad upper 

 part to a cordate base. They are of a bright clear 

 green, but whitish on the undersides. The flowers of 

 these trees are large also — about a foot wide, cream- 

 white except for a purplish cast at the base. They 

 are very fragrant. A little to the northeast of these 

 is another magnolia. This is umbrella tree, which you 

 met with before, on Section No. 3 near the Arsenal. 

 Note the umbrella-way its leaves hang at the ends of 

 its branches. Due north of this tree, close by the 

 Lake, is Virginia willow. It is an interesting shrub, 

 with white flowers in May or June, in close terminal 

 racemes that put you in mind of the sweet pepper 

 bush. The individual flowers have five petals, five 

 stamens, and a five-lobed calyx. Its leaves are simple 

 and alternate, acute at the tip, wedge-shaped at the 

 base. The fruit is a two-celled pod. It belongs to 

 the Saxifrage family, and gets its name from the Greek 

 word for willow, from the resemblance of its leaves to 

 those of the willow. A tree alder stands a little west 

 of this, overhanging the Lake and easily known by its 

 "cones" and leaves somewhat cut-in at the top. West 

 of the alder is cottonwood. Should you continue to- 

 ward the Boat House, at the junction of the Walk 

 beyond, there are two good specimens of American 

 beech with a black cherry opposite them. 

 Let us now consider the westerly side of the Ter- 



