DESCRIPTION OF THE MILK TREE IN SOUTH AMERICA.

M. Humboldt and his companions, in the course of their travels, heard an account of a tree which grows in the valleys of Aragua, the juice of which is a nourishing milk, and which, from that circumstance, has received the appellation of the Cow Tree.

The tree, in its general aspect, resembles the chrysophyllum cainito; its leaves are oblong, pointed, and alternately marked with lateral veins, projecting downwards, they are parallel, and are ten inches long.

When incisions are made into the trunk, it discharges copiously a glutinous milk, moderately thick, without any acridness, and exhaling an agreeable balsamic odour.

The travellers drank considerable quantities of it, without experiencing any injurious effects; its viscidity only rendering it rather unpleasant.

When this fluid is exposed to the air, perhaps in consequence of the absorption of the oxygen of the atmosphere, its surface becomes covered with membranes of a substance that appears to be of a decided animal nature, yellowish, thready, and of a cheesy consistence.

These membranes, when separated from the more aqueous part of the fluid, are almost as elastic as caoutchouc, but at the same time they very soon become putrid.

The natives give the name of cheese to the coagulum which is separated by the contact of the air, in the course of five or six days it becomes sour.

The milk, kept for some time in a corked phial, had deposited a little coagulum, and still exhaled its balsamic smell.

If the recent juice be mixed with cold water, the coagulum is formed in a small quantity only; but the separating of the viscid membranes occurs when it is placed in contact with nitric acid.

This remarkable tree seems to be peculiar to the Cordiliere du Littoral, particularly from Barbula to the lake of Maracaybo.

There are likewise some traces of it near the village of San Mateo; and, according to the account of M. Bredmeyer in the valley of Caucagua, three days' journey to the east of the Caraccas.

This naturalist has likewise described the vegetable milk of the Cow-tree as possessing an agreeable flavour, and an aromatic odour; the natives of Caucagua call it the milk tree.

H. B.