(Plate XXXV.)

This is one of the sturdy dwarf irises, which follows the Al-leghanies and chooses the rocky banks of streams for its dwelling place. It blossoms in April and May and is of a soft violet blue. The flower is spreading, with a much longer tube than that of the I. versicolar. Its outer divisions are prettily crested. The leaves are not conspicuous; lanceolate and clasping.