The fruit is a capsule splitting generally by three longitudinal slits forming valves which remain united above and below.
This is done by scraping the capsule with a knife and transferring the concreted juice to a poppy-leaf held in the left hand, the edges of the leaf being turned in to avoid spilling the juice, and the knife-blade moistened with saliva by drawing it through the mouth after every alternate scraping to prevent the juice from adhering to it.
Egg-capsules are formed they are often of large size, have tough walls, and in each capsule are several eggs floating in a viscid fluid.
In dry weather the valves open, and the small seeds are ejected through the pores when the capsule is shaken by the wind on its long stiff slender stalk.
Bulbous plants with a terminal racemose inflorescence; the anthers open introrsely and the capsule is loculicidal.
Another favourable feature is the fact that a single capsule contains from 4000 to 8000 seeds, and one tobacco plant may easily produce from 500,000 to 1,000,000 seeds.
In modern botany it is a technical term sometimes denoting the lower part of the capsule called pyxidium, attached to the flower stalk in the form of an urn.
The catkins of the poplars differ from those of the nearly allied willows in the presence of a rudimentary perianth, of obliquely cup-shaped form, within the toothed bracteal scales; the male flowers contain from eight to thirty stamens; the fertile bear a onecelled (nearly divided) ovary, surmounted by the deeply cleft stigmas; the two-valved capsule contains several seeds, each furnished with a long tuft of silky or cotton-like hairs.
The fruit is ripe in or shortly before the first week in October, when it falls to the ground, and the three-valved thorny capsule divides, disclosing the brown and at first beautifully glossy seeds, the so-called nuts, having a resemblance to sweet chestnuts, and commonly three or else two in number.
The arrested embryos or eggs are then swallowed and digested by those in the same capsule which have advanced in development.