According to Fernald (1950: Gray's Manual), the generic name derives from an old Latin name of nettle-like plants mentioned by Pliny.
Bernstrom, P. 1950. Cleisto- and chasmogamic seed setting in di-and tetraploid Lamium amplexicaule . Hereditas 36: 492-506.
Lord, E.M. 1980. Physiological controls on the production of cleistogamous and chasmogamous flowers in Lamium amplexicaule L. Ann. Bot. 44: 757-766.
A genus of about 40 species, all of these native to the Old World, but several now common world-wide weeds in disturbed areas. Two species occur in Texas, both of these introduced. Lamium amplexicaule is especially abundant in Texas, occurring as a spring weed in lawns everywhere.
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