DILLENIIDAE  (copy of overhead presented in lab)

This is the fourth dicot subclass--about halfway between primitive Magnoliidae and derived Asteridae.  Unifying characters: None! In members with showy flowers and fused corollas, stamens are usually more than the petals.

1. Malvaceae--Ours usually herbs. Palmate leaf venation and/or lobing; EPICALYX of bracts often subtending calyx, stamens MONADELPHOUS (united by filaments); petals free, carpels some multiple of 5. Ex: Gossypium (cotton) and Callirhoe (winecup).

2.  Salicaceae--Trees or shrubs. Dioecious, both sexes of flowers in catkins; flowers without perianth, subtended by bracts, nectary glands or scales present; ovary bicarpellate, seeds many, comose. Ex: Salix (willow) and Populus (poplar or aspen).

3. Brassicaceae (Cruciferae)--Herbs with watery juice, often biennial; flowers cruciform (cross-shaped), stamens tetradynamous (4 + 2); fruit a silique or silice with 2 locules separated by a replum. Important family with food crops--cabbage, broccoli, cauliflower, kale, kohlrabi--all Brassica oleracea.

4. Ericaceae--Acid loving plants; corolla urceolate or campanulate; stamens often poricidal. Only local genus Vaccinium.  Other ex: Gaylussacia. Many ornamentals, e.g. azaleas.

5. Cucurbitaceae--Vines with tendrils; flowers unisexual, both sexes with nectary disks; stamens united by anthers; ovary inferior, tricarpellate; fruit a pepo with parietal placentation. Ex: Cucumis (cucumber, also melon). Also Cucurbita (squashes, gourds, pumpkins) and Citrullus (watermelon).

6. Carnivorous plants--Plants of acid bogs with low soil nutrients. Plants supplement their "diet" by obtaining nitrogen from digested insects. Sticky traps, pitfall traps, and snap traps are common. Drosera (sundew) and Dionaea (Venus flytrap)--Droseraceae, Sarracenia (pitcher plant)--Sarraceniaceae. Please don't touch!

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last modified Sept. 27, 2000 by MDR