109 
THE DEAD-NETTLE FAMILY 
10. Corn Mint. (Mentha arven'sis. Linn.)— This, like the Marsh Whorled Mint 
(Mentha gentilis), varies extraordinarily, and the last London Catalogue gives eight varieties of it. 
It has, however, one feature which is fairly constant and distinguishes it from the 3 preceding 
species, that is the short bell-shaped (campanulate) calyx with short triangular (deltoid) teeth. 
[As described in the genus Mint (Mentha).] The flower-clusters are, as in the Marsh Whorled 
Mint (Mentha gentilis), in dense distant clusters in the axils of the leaves, the terminal leaves 
being empty, without any flowers ; the corolla is hairy both outside and in ; the stems are usually 
half prostrate, 6-18 inches long, rarely erect, much branched, spreading, and more or less hairy; 
and the leaves are stalked, egg-shaped (ovate), toothed (serrate), and hairy. 
Common. In corn-fields and waste places ; in England, Scotland, and Ireland. July — September. 
Perennial. 
11. Pennyroyal. (Men tha Pulegrium. Linn.)— This is the smallest species we have 
and is very different in habit from those already described. The flowers are £ inch long, purplish- 
rose, in dense distant clusters in the leaf-axils (false whorls), the clusters and leaves getting 
smaller at the top of the stem ; the calyx is tubular and the teeth rather unequal, the mouth of the 
tube being closed with hairs ; the corolla is hairy outside ; the stem is 3 inches to 1 foot long, 
usually prostrate but with an erect variety ; the leaves are smaller than in any other species of this 
genus and are shortly stalked, egg-shaped (ovate), entire and wavy or slightly scalloped (crenate). 
The whole plant has a very pleasant scent, and is sometimes nearly smooth (glabrous) and 
sometimes densely hairy. 
Not common. By wet ditches, on banks and damp heaths ; sparingly spread over England and 
Ireland, rare in Scotland. July — September. Perennial. 
