The trees are regularly tapped and the coagulated latex which exudes is collected and worked up into rubber.
The mucins and mucoids belong to this group; they are acid and contain no phosphorus; they give the albumin colour reactions but are not coagulated by heat.
A remarkable change occurs when many albumins are boiled with water, or treated with certain acids, their solubility and general characters being entirely altered, and the fluid becoming coagulated.
The globulins are insoluble in water and in dilute acids, but soluble in alkalies and in neutral salt solutions; these solutions are coagulated on boiling.
In general they resemble coagulated albumin, and also the gelatin-yielding tissues, but they themselves do not yield gelatin.
