MINT FAMILY 209 



1. C. americana L. French Mulberry, Mexican Mulberry. 

 Shrubs, with star-shaped glandular or scurfy down, widely branched, 

 3-8 ft. high. Leaves ovate to oblong, acute at each end, crenate- 

 serrate, rough above, downy beneath, glandular-dotted ; petioles slen- 

 der. Cymes many-flowered, the peduncle as long as the petiole ; 

 pedicels short. Calyx cup-shaped, the teeth short. Corolla double 

 the length of the calyx, blue. Fruit violet-purple, very conspicuous 

 in autumn. Common in fields and thickets S.* 



88. LABIAT.ffi. Mint Family 



Mostly herbs, with square stems and opposite, more or less 

 aromatic, leaves, without stipules. Flowers generally in cyme- 

 like axillary clusters, which are often grouped into terminal 

 spikes or racemes; Calyx tubular, usually 2-lipped, persistent. 

 Corolla usually 2-lipped. Stamens 4 (2 long and 2 short) or 

 only 2. Ovary free, with 4 deep lobes, which surround the 

 base of the style. Fruit consisting of 4 nutlets, ripening 

 inside the base of the calyx. 



Stamens 4- 



(a) Calyx 2-lipped. 



Lips entire. Scutellaria, I 



Lips toothed and cleft. Plants not aromatic. Prunella, IV 



Lips toothed and cleft. Plants aromatic. Leaves extremely 



small. Thymus, IX 



(6) Calyx not 2-lippea, or not much so. 



Calyx tubular, 5-10-toothed. Stamens not projecting from 



tube of corolla. Marrubium, II 



Calyx tubular, with 5 equal teeth. Stamens under upper 



lip of corolla. Nepeta, III 



Calyx tubular, bell-shaped, with 5 awl-shaped teeth. Stamens 



not turned down after maturing. Lamium, V 



Calyx top-shaped, with spreading spiny teeth. Leonurus, VI 



Calyx as in V. Stamens turned down after maturing. 



Stachys, VII 



B 



Stamens 2. Salvia, VIII 



