N. ORD.—CRUCIFERZ. ee 23 
Tribe.—BRASSICEA. S 
GENUS.—SINAPIS, TOURN. 
SEX. SYST.—TETRADYNAMIA SILIQUOSA. 
SINAPIS ALBA. 
WHITE MUSTARD. 
SYN.—BRASSICA ALBA, HOOK, f.; SINAPIS ALBA, LINN. ; LEUCOSINAPIS 
ALBA, SPACH. 
COM. NAMES.—WHITE OR YELLOW MUSTARD ;* (FR.) MOUTARDE BLANC : 
(GER.) WEISSER SENF. 
A TINCTURE OF THE RIPE SEEDS OF SINAPIS ALBA, LINN. 
Description.—This coarse, hairy annual, usually grows to a height of about 
2 feet. Stem erect; branches few, ascending, all parts covered with bristling re- 
flexed hairs. eaves all petioled and pinnatifid, the lowest having a large termi- 
nal lobe and the divisions cutting down to the midrib. Flowers about twice as 
large as those of S. nigra; sepals 4, narrowly oblong, spreading; petals 4, spread- 
ing, alternate with the sepals, and consisting of a narrow claw and an orbiculate 
blade. Stamens 6, hypogynous, tetradynamous, the two having shorter filaments 
being lateral and inserted lower down than the others, the four with longer fila- 
ments situated in pairs from before backward and accompanied by a quite large 
gland to each pair. Fist? slightly exceeding the stamens; ovary hairy; style 
nearly terete, persistent; s#gma bi-labiate. /7uit a linear, bristly, ascending 
silique ; valves short, furnished with 3 prominent veins; fedicels spreading ; beak 
sword-shaped, 1-seeded, about half the length of the pod. Seeds globular, pale- 
yellowish, 1 to 6 in each pod; cotyledons incumbent, conduplicate, narrow, and 
plane. ° ; 
Cruciferge.—This large family of pungent and often acrid herbs is represented 
in North America by 42 genera, containing in all 275 species and 50 recognized 
varieties, The order is characterized as follows: Leaves alternate ; s/fules none. 
Inflorescence in terminal racemes or corymbs; flowers cruciform, tetradynamous. 
Sepals 4, deciduous; petals 4, hypogynous, regular, placed opposite each other in 
pairs. Stamens 6, rarely 4 or 2, when 6, then two are inserted lower down than 
the rest and furnished with shorter filaments. /ywit a 2-celled silicle, loment, 
silique or necument. Seeds campylotropous; eméryo large; albumen none; coty- 
gedons incumbent o||, acumbent o=, or conduplicate 0)), being straight in one 
genus only, 
= 
* The name mustard is modernized from mustum ardens, hot must; as wine-must is often mixed with the seed- 
Meal in the manufacture of table mustard. ; 
