1 Achenes 8 - ribbed, white pilose; pappus scabrous, 10 - 12 mm long, connate at base.

2 After dispersal, the short pappus of the achenes can adhere to the wet soil surface so that the achenes remain near the dead mother plant and germinate there.

3 The seeds often furnished with apical pappus , can act as parachutes for wind-dispersal.

4 Parachute n. special structure of seeds such us aril, caruncle, pappus , or wing, which aids dispersal by wind; a fold of skin used for gliding as in flying squirrels.

5 Some examples are given by inscribed and circumscribed circles of polygons, lines intersecting and tangent to conic sections, the Pappus and Menelaus configurations of points and lines.

6 The third and fourth chapters introduce the famous theorems of Desargues and Pappus.