382 =... - DIDYNAMIA. GYMNOSPERMIA. 
~e 
Calix 5-cleft, subequal. Anthers approach- 
ing each other in pairs, each pair producing the 
form of a cross. 
Creeping herbaceous and aromatic plants; peduncles 
axillary about 3-flowered, flowers blue. Corolla double 
the length of the calix, upper lip bitid, lower trifid, mid- 
dle segment larger and emarginate. 
Srecies. 1. G. hederacea. Probably indigenous;— 
abundant along the banks of the Ohio, the Potomac, &c. 
remote from settlements, flowers —_ and brighter 
than the European species- 
Of this genus there is now a second species described 
as growing in the woods of Hungary. 
07. MARRUBIUM. ZL. (White Horehound.) 
Calix salverform, rigid, 10-striate. Upper 
lip of the corolla bifid, linear, straight. 
Flowers verticillate, sessile; bractes numerous, linear. 
Leaves mostly whitish and rugosely veined. Calix in ma- 
ny species 10-toothed. 
Species. 1. M. vulgare. Naturalized.—A small ge- 
incipally indigenous to the south of Europe and the 
Jacquin. 
thed. Corolla bilabiate: upper 
ower 3-lobed: intermediate lobe cal- ~ 
first involving the style and sta- 
ina, afterwards reflected. Siamina declinate. 
we . 
ape aN SoC aa ee = NRA Ree OE 
Herbaceous; flowers rapitate, rarely subcymose pani- 
- eulately spiked or axillary; capituli involucrate. 
Specizs. 1. H. capitata. 2. radiata--A 2 ad genus 
ie Ameria 3h Ce ere: Ad. persica. A 
ny bractes.—Calia tubular, striate 5- toothe 
= Copitalum pucroundel by an inves of a 
a of the corolla nearly entire; lower t 
