Alstonia scholaris

The tree grows from 50 to 80 feet high, has a furrowed trunk, oblong stalked leaves up to 6 inches long and 4 inches wide, dispersed in four to six whorls round the stem, their upper side glossy, under side white, nerves running at right angles to the mid-rib. The bark is almost odourless and very bitter, in commerce it is found in irregular fragments 1/8 to 1/2 inch thick, texture spongy, fracture coarse and short, outside layer rough uneven fissured brownish grey and sometimes blackish spots; inside layer bright buff, transverse section shows a number of small medullary rays in inner layer.