The hump (or humps) varies in size according to the condition of the animal, becoming small and flaccid after hard work and poor diet.
On stimulation these cells part with their water, the lower side of the organ becomes flaccid and the weight of the leaf causes it to fall.
The first is flaccid and sluggish in its movements, and has not much power of contraction; its epipodial lobes are enormously developed and extend far forward along the body; it gives out when handled an abundance of purple liquid, which is derived from cutaneous glands situated on the under side of the free edge of the mantle.
Cut plants are allowed to wilt, or become flaccid, before removal from the field, to prevent injury to the turgid leaves.
They are then spread out thinly on trays or racks made of bamboo, canvas or wire netting, under cover, for some 18 or 30 hours (according to the temporary weather conditions) to wither, after which they are in a soft, flaccid condition ready for rolling.