This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Herbs, with dentate or incised leaves, and mostly white or blue rather small flowers in verticillate clusters, usually crowded in terminal spikes, or axillary and cymose. Calyx tubular, somewhat oblique at the mouth, 15-nerved, usually incurved, 5-toothed, scarcely 2-lipped, but the upper teeth usually longer than the lower. Corolla-tube enlarged above, the limb strongly 2-lipped; upper lip erect, emarginate or 2-lobed; lower lip spreading, 3-lobed, the middle lobe larger than the lateral ones. Stamens 4, all anther bearing, didynamous, ascending under the upper lip, the lower pair the shorter; anthers 2-celled, the sacs divaricate. Ovary deeply 4-parted; style 2-cleft at the summit. Nutlets ovoid, compressed, smooth. [Ancient Latin name of catnep.]
About 150 species, natives of Europe and Asia, the following typical.

Fig. 3594
Nepeta Cataria L. Sp. Pl. 570. 1753.
Perennial, densely canescent, pale green; stem rather stout, erect, branched, 2°-3° high, the branches straight, ascending. Leaves ovate to oblong, petioled, acute at the apex, coarsely cre-nate-dentate, mostly cordate at the base, 1'-3' long, greener above than beneath; flower-clusters spiked at the ends of the stem and branches, the spikes 1'-5' long; bracts small, foliaceous; bract-lets subulate; calyx puberulent, its teeth subulate, the upper about one-half the length of the tube; corolla nearly white, or pale purple, dark-dotted, puberulent without, 5"-6" long, its lobe a little longer than the calyx, the broad middle lobe of its lower lip crenulate.
In waste places, New Brunswick and Quebec to South Dakota, Oregon, South Carolina, Kansas and Utah; also in Cuba. Naturalized from Europe. Native also of Asia. July-Nov.
 
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