As we picked our way along slowly and painfully, frequently wading through water three feet deep, a dark, shadowy form lunged from the blackness of a cavern among the boulders and clung for an instant to the cuff of my hunting-coat; then it dropped to the ground, and slowly disappeared among the rocks. My companion, who was a few feet in advance, had just turned to make some comment, and it was not until his frantic shriek brought me back to earth that I fully realized what had occurred. A bushmaster, apparently four or five feet long had become exasperated at our close proximity, and aimed a deadly thrust at the disturber of its diurnal slumber. This habit of the snake is well known; by nature it is sluggish; one person may pass close by without arousing its anger, while to a second individual, immediately following, it will show resentment, although it may not strike; but a third may consider himself fortunate, indeed, if he does not draw the full measure of the reptile’s fury. The exploration at Alto Bonito yielded such rich returns that we regretted the necessity of leaving; but a field-naturalist’s time is not unlimited, and presently we found ourselves riding across the parched Antioquian desert, _en route_ to Medellin. The work at Alto Bonito provided the last link in the chain of facts regarding the forestation of northwestern Antioquia, and also throws some light on the extension of the mountain ranges. For information on the latter subject we were compelled to rely largely on data furnished by Señor Cspinas, director of the School of Mines, Medellin; Señor Ernesto White, an engineer who has made surveys in the region, and the reports of Indians. The Western Cordillera terminates in the Cerro Aguila, just below 9°, near the Golfo de Urubá, and is less than one thousand feet high. The range breaks down, gradually, north of the Paramillo. In latitude 7½° the highest peak is known as Alto Esmeralda, four thousand feet high; and the Abibi, a few miles farther north, reaches an altitude of only three thousand six hundred feet. A trail recently built (by Señor White) from Turbo on the Gulf of Urubá to Montana on the Rio Sinú crosses the very country about which we knew least; the elevation of its highest point is eight hundred feet, and every mile of the way was cut through heavy virgin forest. _PART II_ VENEZUELA CHAPTER X FIFTEEN HUNDRED MILES ON THE ORINOCO