This species of St. John's-Wort, particularly distinguished
by the largeness of its flowers, has very generally been con-
sidered as the Ascyron of LINNÆUS, owing to his giving to
that plant the synonyms which properly belong to the present
one: in his Mantissa, this species is called calycinum, which
name is adopted in the 14th edition of the Systema Vegetabilium, and also in the Hortus Kewensis, where the proper synonyms are applied to it, and from which we learn, that it is a native of the country near Constantinople, and was introduced into this country by Sir , Bart. in 1676.
It is a hardy perennial, increasing much by its roots, which
are of the creeping kind, and by parting of which in the
autumn it is most readily propagated; like the periwinkle, it
is a plant well adapted to cover a bank, or bare, spots under
trees, where other plants will not thrive.
It flowers from July to September.