The climate, like that of the Amazon country, is humid and hot, with a rainy and a dry season. The southerly situation, however, causes a somewhat more marked difference between the two seasons. In April, the rains become less frequent and then, until October, there are no or but very few heavy precipitations; some times the fallen leaves on the ground in the woods are dried out and even the dew is absent. There then occur, however, especially in the months of June, July and August, steady cold spells, when the thermometer, in the morning, sinks to 8° C. and often does not go above 12° C. during the day. These so-called =Friazens= last several days and are recurrent, but cease in September. Thunder storms and violent rain storms begin in October, so that in November the rivers are usually navigable again. In December the first steamships arrive. In January and February a rainless period is frequent, which is followed, in March and April again, by a rainy spell. Many steamers undertake, usually at this time, their second voyage and if they have good fortune they make three trips to upper Acre. The copious precipitation, the heat and the fertile soil have produced in Acre a luxuriant primeval forest, which is higher and more densely overgrown than that of the lower river courses of the Amazon country. Trees of 40 to 50 meters in height are not infrequent, they form a forest of varied composition. There may be found here representatives of the most diverse plant families; some of which, in the cool season, lose their foliage. The forest is densely overgrown with plants, shoots and shrubs. Where a thorny growth, Tapoea and other underbrush gets the upper hand, a macheté or axe is necessary in forcing a path through the virgin forest. Various kinds of trees are used by the natives for building houses, fashioning canoes and other purposes. For export, however, neither these useful woods nor many other products of the forest, have attained any importance. The fruit of the cacao tree and Pará nuts, rot on the ground, transportation to Manáos being too costly. The caoutchouc products are, however, present in such abundance and possess such great value, that their acquisition and transportation recompenses every effort and have been the cause of the development in these distant primeval forests of a busy life. The water in the deeply hollowed bed of the Acre, swells in flood time and submerges the land on the adjacent shores and some sand banks, but for the most part does not penetrate into the forest or only for a short period. The flooded forests of the lower water courses, often miles in extent, are lacking and the fine rubber trees grown on land free from inundation, often reaches up into the hills in the hilly or mountainous district. [Illustration: JUNCTION OF THE ACRE RIVER WITH THE PURÚS.]