ASTERACEAE (Lactuceae) -
Lactuca sativa L., Cichorium intybus L., Taraxacum officinale G. Weber, Tragopogon pratensis L.

Lettuces (Tribe Lactuceae) derive their name from the Latin for "milky," in recognition of the way in which they are copiously supplied with latex ducts as a deterrent to herbivores. Thousands of years of selection have bred out the most unpalatable components of this latex in the cultivated lettuces. Some of these components have sedative properties. Both aphrodisiac and anaphrodisiac properties have been ascribed to lettuces (Visser 1986; Mabberley 1997).

Lactuca sativa L. - romaine lettuce

Photo: ©2001 T. A. Dickinson

Cichorium intybus L.

Ligulate capitula are another feature of Tribe Lactuceae; each flower has a ligulate corolla.

Cichorium intybus L. - chicory. Roots are used to adulterate (or substitute for) coffee; endive (one of the bitter herbs of Passover) is C. endiva L. (Mabberley 1997).

Photo: ©2001 T. A. Dickinson

More images of C. intybus can be found HERE, including ones that show pollen grains on the stigmas in great detail (Brian Johnston MICscape article).

Taraxacum officinale G. Weber (20558 bytes) Taraxacum officinale G. Weber (dandelion)

Photo: R. Presgrave 1997 Royal Ontario Museum (TRT 3716)

Tragopogon

    pratensis L. Detail of fruiting

    capitulum (21222 bytes) Tragopogon pratensis L. (goatsbeard) Detail of fruiting capitulum. The individual fruits are achenes.

Photo: R. Presgrave 1997 Royal Ontario Museum (TRT 3722)

Tragopogon pratensis L. 

    pappus (18949 bytes) Tragopogon pratensis L. (goatsbeard) pappus.

Photo: R. Presgrave 1997 Royal Ontario Museum (TRT 3726)

 

Visser, M. 1986. Much depends on dinner. McClelland & Stewart, Toronto.


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