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 Various Forms of Corolla.—The corolla often assumes very definite or distinct forms, especially when gamopetalous. It may have a long tube with a wide-flaring limb, when it is said to be funnelform, as in morning-glory and pumpkin. If the tube is very narrow and the limb stands at right angles to it, the corolla is salverform, as in phlox. If the tube is very short and the limb wide-spreading and nearly circular in outline, the corolla is rotate or wheel-shaped, as in potato.

A gamopetalous corolla or gamosepalous calyx is often cleft in such way as to make two prominent parts. Such parts are said to be lipped or labiate. Each of the lips or lobes may be notched or toothed. In 5-membered flowers, the lower lip is usually 3-lobed and the upper one 2-lobed. Labiate flowers are characteristic of the mint family (Fig. 185), and the family therefore is called the Labiatæ. (Literally, labiate means merely "lipped," without specifying the number of lips or lobes; but it is commonly used to designate 2-lipped flowers.) Strongly 2-parted polypetalous flowers may be said to be labiate; but the term is oftenest used for gamopetalous corollas.

Labiate gamopetalous flowers that are closed in the throat (or entrance to the tube) are said to be grinning or personate (personate means masked, or person-like). Snap-dragon is a typical example; also toadflax or butter-and-eggs (Fig. 186), and many related plants. Personate flowers usually have definite relations to insect pollination. Observe how an insect forces his head into the closed throat of the toadflax.