MENTZELIAS 223 
what heart-shaped, angled, opposite, without stalks. Flowers solitary, 
yellow ; June to August. ual. 
L. VULCANICA (volcanic). Stems erect, 3 feet high. Leaves with 
three to five cut lobes, arranged palmately. Flowers about 14 inch 
across; petals white; scales red striped with white and yellow ; June to 
August. Annual. 
All the cultivated species whether annual or perennial 
are generally treated as annuals, for summer bedding. The 
seeds are sown, in March, in pans of light sandy soil, and these placed in 
gentle heat; or out of doors in a sunny border in May. When sufficiently 
grown the seedlings should be planted out at distances regulated by the 
erect or climbing habit of the species. They do best in light soils with 
a sunny position; otherwise requiring no special treatment. Where it 
is desired to grow the perennials as perennials, they must be lifted early 
in October and wintered in a cool greenhouse. In handling the plants, 
care should be taken to avoid being stung by the hairs, which are similar 
in their action and effects to those of our native Stinging Nettles. 
Description of The upper portion of the stem of Loasa lateritia with 
Plate 109. eaves, unopened bud, expanded flower, flower from which 
the petals have fallen, and the twisted capsule. Fig. 1 is a section 
through the flower; 2, the seed, natural size and enlarged ; 3, a seedling. 
Cultivation. 
MENTZELIAS 
Natural Order LoasEx. Genus Mentzelia 
MENTZELIA (named in honour of Christian Mentzel, a botanist of 
Brandenburg, 1622-1701). A genus of herbaceous plants, with coarsely 
toothed, alternate or nearly opposite leaves, and orange or white flowers, 
which in most species expand only under direct influence of the sunshine, 
though several on the contrary wait until evening before opening. They 
differ from Loasa chiefly in the absence of the large scales from between 
the petals, the flatness of the latter, the more numerous stamens, and in 
the seed-vessel being untwisted. The plants, though not free from hairs, 
do not sting. The species are all American. 
The most familiar species of Mentzelia are better 
known under the name of Bartonia, in which genus certain 
of them were formerly comprised. The plant figuring in seedsmen’s 
catalogues as Bartonia aurea is more correctly named Mentzelia Lindley. 
The first species to be introduced was M. aspera from the United States 
History. 
