As a rule, the Rhynchites works backwards. When her line is finished, she is careful not to abandon the fold which she has just made in order to return to the starting-point and begin another. The part last folded is not yet sufficiently subdued; if left to itself too soon, it might prove rebellious and flatten out again. The insect therefore continues at this extreme point, which is more exposed than the rest, and then, without letting go, makes her way backwards to the other end, always with patient deliberation. In this manner, an added firmness is imparted to the new fold; and the next fold is prepared. At the end of the line, there is a fresh prolonged halt and a fresh move backwards. Even so does the husbandman plough the furrows in alternate directions. Less frequently, no doubt when the leaf is found to be so limp as to entail no risk, the insect abandons the fold which it has just made, without going over it again conversely, and quickly scrambles back to the starting-point to make another. Here we are at last. Coming and going from top to bottom and from bottom to top, the insect, by dint of stubborn dexterity, has rolled its leaf. It is now at the extreme edge of the leaf, at the lateral corner opposite to that whereat the work began. This is the keystone on which the stability of the rest depends. The Rhynchites redoubles her efforts and her patience. With the tip of her rostrum, expanded spatula-wise, she presses, point by point, the edge to be fixed, even as the tailor presses the rebellious edges of a seam with his iron. For a long, a very long time, without moving, she pushes and pushes, awaiting a proper degree of adhesion. Point by point, the whole welt of the corner is minutely and carefully made fast. How is adhesion obtained? If only some sort of thread were employed, one might very well regard the rostrum as a sewing-machine, inserting its needle at right angles into the stuff. But the comparison is not permissible: there is no filament employed in the work. The explanation of the adhesion lies elsewhere. The leaf is young, we said; the fine pads of its denticulations are glands emitting traces of liquid glue. These drops of sticky matter are the gum, the sealing-wax. By the pressure of its beak, the insect makes it flow more abundantly from the glands. It then has only to hold the signet in position and wait for the viscous seal to set. Taken all round, this is our own method of sealing a letter. If it holds ever so lightly, the leaf, losing its resilience as it gradually withers, will soon cease to react and will of itself retain the cylindrical shape imposed upon it.