unless actually struck or stepped upon are apt to try to get out of the way, if they make any move. The only snake that is at all aggressive, as far as my observations go, is a long, black, non-poisonous snake. This will sometimes advance upon the intruder with head raised a couple of feet from the ground, or if coiled about a tree will lash at him with its tail. The floral exhibit of these forests is apt to be disappointing to one whose ideas have been formed by a perusal of books. An occasional scarlet passion flower; now and then the fragrant cluster of the _flor del toro_; a few insignificant though fragrant flowering shrubs; and in muddy sloughs near the streams, patches of wild callas; are about all that meet the eye of the non-botanical wanderer in the deep forest. There is not light enough for flowers beneath the dense canopy of trees, and they, like the smaller birds, seek the tree tops and the banks of the river where sunlight and air are abundant. In the tree tops the orchids and other flowering parasites run riot. Many of the trees are themselves flowering, and if one can look down upon the tree tops of a valley in March or April, he sees the green expanse enlivened by blazing patches of crimson, yellow, purple, pink, and white. The river banks are the favorite home of the flowering vines, and there they form great curtains swaying from the trees in bright patterns of yellow, pink, red and white. The grassy banks and islands, and the shallow sand spits also bring forth innumerable varieties of aquatic plants. So much for the Atlantic slope of the country. On the west side between the Lake and the Pacific the work is very different. There it is possible to ride mule-back to the top of a commanding hill, sit down and make the reconnaissance sketch at leisure. The secondary reconnaissances may also be made mule-back, and everywhere the rolling country and the cleared and cultivated fields, permit the engineer to see where he is going and how he is going. His surroundings are also different. He moves camp in an oxcart instead of a canoe. His eyes instead of being confined by the impenetrable veil of the tropical thicket, feast upon views of the distant mountains, the crisp waves of the Lake, and the blue expanse of the Pacific. During the day he meets black-eyed and brown-limbed señoritas, instead of wild hogs and turkeys, and at night as he turns in, he hears, not the scream of tigers, but the songs of the _lavandera's_ ecru daughters floating across the stream which supplies their wash-tubs and his camp.