be observed extending along the surface of the ground forty or fifty yards from the trunk, also retain their vitality after the tree is laid low; and the Portuguese now know that the best way to treat them is to let them alone, for they occupy much more room when cut down than when growing. The wood is so spongy and soft that an axe can be struck in so far with a good blow that there is great difficulty in pulling it out again. In the dead mowana mentioned the concentric rings were well seen. The average for a foot at three different places was eighty-one and a half of these rings. Each of the laminae can be seen to be composed of two, three, or four layers of ligneous tubes; but supposing each ring the growth of one year, and the semidiameter of a mowana of one hundred feet in circumference about seventeen feet, if the central point were in the centre of the tree, then its age would lack some centuries of being as old as the Christian era (1400). Though it possesses amazing vitality, it is difficult to believe that this great baby-looking bulb or tree is as old as the Pyramids. The mopane-tree ('bauhinia') is remarkable for the little shade its leaves afford. They fold together and stand nearly perpendicular during the heat of the day, so that only the shadow of their edges comes to the ground. On these leaves the small larvae of a winged insect appear covered over with a sweet, gummy substance. The people collect this in great quantities, and use it as food;* and the lopane--large caterpillars three inches long, which feed on the leaves, and are seen strung together--share the same fate. * I am favored with Mr. Westwood's remarks on this insect as follows: "Taylor Institution, Oxford, July 9, 1857.