42 
Dicotyledons with Polypetalous Flowers. 
Natural Order 
LYTH RACEME. Tab. 34. 
Diagnosis. —Herbs (or shrubs), usually with opposite leaves. Calyx 
tubular or campanulate. Stamens perigynous, usually definite. Ovary free, 
with 2 or more cells and indefinite ovules ; style 1. 
Distribution. —The woody genera are chiefly Tropical, while many of the herbaceous genera, 
especially those affecting marshy localities, are cosmopolitan. 
Number of British Genera, 2 ; Species, 3. 
Calyx in Purple Loosestrife (Lythrum) with twice as many teeth as petals. 
Petals equal; or unequal in Guphea. 
Stamens in Loosestrife in two unequal series, and never equal in length to the pistil, in the same plant. Mr. 
Darwin has shown that the species is most productive of good seed when the pistil is fertilised by pollen transferred 
from stamens corresponding in length to the pistil. As these are necessarily borne upon a distinct plant the trans¬ 
ference can only take place through adventitious, especially insect, agency. 
USES, &c.—None are of much economic importance. Henna, a dye used by Mahometan ladies to dye their 
nails, &c., consists of the powdered leaves of Lawsonia inermis. Species of the American genus Guphea are in 
garden cultivation. 
