This section is from the book "Who's Who Among The Wild Flowers", by W. I. Beecroft. Also available from Amazon: A Field Guide to Edible Wild Plants.
Helmet Flower: Madweed: Hoodwort. Scutellaria lateriflora.
Mint Family. July - Sept.
A plant 1 - 2 feet high, found in damp, shady places throughout the United States and northward.
Blue or purple, varying to whitish, small, about 1/4 inch long, growing in 1-sided spikes from the angles of the upper leaves.
Opposite, pointed, rounded at the base, coarsely toothed. 1 - 2 feet high.

Mad-dog Skullcap.
Larger or Hyssop Skullcap.
Scutellaria integrifolia. Mint Family. May - Aug.
Found in borders of fields and woods. Massachusetts to Florida and Texas, chiefly near the coast.
Blue, about 1 inch long, opposite each other at the top of a stem 6 - 20 inches high.
Oblong or narrower, mostly toothless. Plant stem and leaves covered with a fine down.

Skullcap.
 
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