CAMPANULACEAE

The family Campanulaceae (also bellflower family) contains nearly 2400 species in 84 genera of herbaceous plants, shrubs, and rarely small trees, often with milky sap.  Among them are several familiar garden plants belonging to the genera Campanula (bellflower), Lobelia, and Platycodon (balloonflower). Campanula rapunculus (rampion or r. bellflower) and Codonopsis lanceolata are eaten as vegetables. Lobelia inflata (indian tobacco), L. siphilitica and L. tupa (devil's tobacco) and others have been used as medicinal plants. Campanula rapunculoides (creeping bellflower) may be a troublesome weed, particularly in gardens, while Legousia spp. may occur in arable fields.

This family is almost cosmopolitan, occurring on all continents except Antarctica. In addition, species of the family are native to many remote oceanic islands and archipelagos. Hawaii is particularly rich, with well over 100 endemic species. Continental areas with high diversity are South Africa, California, and the northern Andes.

Habitats range from extreme deserts to rainforests and lakes, from the tropics to the high Arctic (Campanula uniflora), and from sea cliffs to high alpine habits.

Flowers are bisexual (dioecious in Dialypetalum) and protandrous. Petals are fused into a corolla with 3 to 8 lobes. It may be bell- or star-shaped in subfamily Campanuloideae, while tubular and bilaterally symmetric in most Lobelioideae. Blue of various shades is the most common petal color, but purple, red, pink, orange, yellow, white, and green also occur. 

Stamens are equal in number to, and alternating with the petals. Anthers may be fused into a tube, as in all species of Lobelioideae and some Campanuloideae.

The style is in various ways involved in the "presentation" of the pollen, as in several other families of the order Asterales. In Lobelioideae, pollen is, already in the bud stage, released into the tube formed by the anthers. During flowering, it is pushed up by the elongating style and "presented" to visiting pollinators at the apex of the tube, a mechanism described as a pollen pump. The style eventually protrudes through the anther tube and becomes receptive to pollen. In Campanuloideae, the pollen is instead packed between hairs on the style, gradually being released as the hairs invaginate. Subsequently, the stigmatic lobes unfold and become receptive.

Bees and birds (particularly hummingbirds and hawaiian honeycreepers) are probably the most common pollinators of Campanulaceae. A few confirmed and many probable cases of bat-pollination are known, particularly in the genus Burmeistera. Brighamia and Hippobroma have pale or white flowers with a long-tubed corolla, and are pollinated by hawkmoths. Pollination by lizards has been reported for Musschia aurea and Nesocodon mauritianus.