56 PLANT LIFE OF ALABAMA. 
Bay. About one-half are native in the West Indies, Mexico, southern 
Brazil, and Argentina; one-fourth are arrivals from the Mediterranean 
region and tropical regions of the Old World, and the rest are from 
central and western Europe. . 
Of the trees and shrubs introduced into cultivation in Alabama a 
comparatively small number have escaped. Such are rarely found 
to stray far from the localities where they have been cultivated, and 
they establish themselves mostly among the native plants along fences, 
about dwellings, on the borders of adjacent woodlands, and in hedge- 
rows. Still smaller is the number which have escaped of the orna- 
mental herbaceous exotic plants cultivated in our gardens. A few 
spring up voluntarily one season after another within the inclosure, 
such as Ami mujus, Ageratum mexicanum, Adicea microphylla her- 
niarioides, but are never found outside of them, while a few others 
stray into the adjacent fields and waste places, the principal examples 
being: 
Ipomoea purpurea. Viola tricolor. 
(Quamoclit quamoelit. Perilla frutescens. 
Gynandropsis pentaphylla. Gemmingia chinensis. 
More numerous are the escapes from the gardens of potherbs, medic- 
inal herbs, and otherwise useful plants. . Such are: 
Mentha piperita (peppermint) . Cnicus benedictus (blessed thistle) . 
Mentha spicata. Chrysanthemum parthenium (feverfew) . 
Mentha rotundifolia. Artemisia vulgaris (mugwort). 
Nepetu caturia (catnip). Leonurus cardiaca (motherwort) . 
Marrubium vulgare (hoarhound). Ricinus communis (castor bean). 
The greatest number of species escaped from cultivation or acci- 
dentally introduced belong to the grasses, which make up fully one- 
fifth of the naturalized plants. These are mostly abundant and 
widely diffused, covering large areas and forming a conspicuous fea- 
ture among the associations of the indigenous plant. Prominent 
species are: 
Syntherismu sanguindle (crab grass). Dactyloctenium aegyptiacum (Egyptian 
Capriolau dactylon (Bermuda grass) . crowfoot). 
Paspalum compressum (carpet grass) . Paspalun dilatatum (hairy-flowered pas- 
palum). 
PLANT DISTRIBUTION IN ALABAMA. 
In several instances, the boundaries of the life zones and areas, 
based upon the distribution of heat and moisture on this continent, 
as established by Merriam, can not at present be distinctly drawn in 
Alabama. The investigation of the plant covering of the State, the 
location of species, and the study of their relation to the factors 
controlling their distribution within its limits is as yet not sufficiently 
