Corydalis formosa and Corydalis canadensis. 115 
ous to this neighborhood ; and so far, I have not had a doubt of their 
being very distinct species. 
Valuable specific distinctions may sometimes be found in the roots 
of plants; and though such are rarely wanted, yet when doubts of 
the distinctness of two species arise, a resort to such characteristics 
may settle the question. ‘Thus tubers are attached to the roots of 
C. canadensis, nearly globular, and so much resembling the grains 
of yellow maize which occur near the ends of the ears, that the pop- 
ular name for this plant is “squirrel corn.” —C. formosa, on the con- 
trary, has a scaly bulb; and a reference to the drawings ill show 
them to be remarkably distinct. 
In all our specimens of C. canadensis, there is only one leaf; but 
in C. formosa the leaves are numerous; the leaf-stalks, rising on all 
sides from the crown of the root, and which in this manner is grad- 
ually elongated. New shoots from the sides of the primary, also pro- 
trude, partially supported by their own roots; and in consequence, 
the plant is readily increased by division. 
The difference in the shape of the leaf-stalks, is not less remark- 
able. In C. canadensis it is terete; in C. formosa, deeply chan- 
neled on the upper side, becoming greatly enlarged and even winged, 
near its base. 
The segments of the leaves in C. canadensis are linear; but in C. 
formosa, these are “ oblong and incisely pinnatifid.” 
The racemes are widely different, being compound in the latter, 
and simple in the former. 
I know of no difference produced in these plants by cultivation. 
C. canadensis grows naturally in the richest soils; and instead of any 
enlargement of its parts, I have found it rather to deteriorate in the 
garden. 
Another consideration might be conclusive with such botanists as 
have cultivated or closely observed the peculiar constitutional tem- 
peraments of plants. I am not aware that any treatment adopted by 
gardeners, has ever caused such as are exclusively vernal, to veget- 
ate and blossom through the summer. All the showers of the finest 
growing season, have never been able in my garden to start a snow- 
drop or a crocus, a tulip or a hyacinth, from its dormant state. The 
law appears'to be as irrevocable as the law of the seed which gives 
form to the future plant; and it may therefore, with great propriety, 
be taken as a part of the specific character. C. canadensis is strict- 
ly vernal. About the close of spring it disappears, leaving not a 
