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PHARMACOGNOSY. 
lowish ; it contains besides tannin a yellow glucosidal 
principle quercitrin, which yields quercetin, a yellow 
coloring principle. 
ULMUS ( Slippery-Elm Bark). 
The bark of Ulmus fulva (Fam. Ulmacese), a tree 
indigenous to the Eastern and Central United States 
and Canada. The bark is collected in spring, deprived 
of the periderm and dried, the commercial article 
coming chiefly from Michigan. 
Description. — In flat oblong pieces about 30 cm. 
long, 10 to 15 cm. in diameter, 3 to 4 mm. thick ; outer 
surface light brown, longitudinally wrinkled and 
furrowed and with occasional dark-brown patches of 
periderm; inner surface yellowish or light brown, 
more or less uniformly wrinkled longitudinally ; frac- 
ture fibrous, surface light brown, porous from large 
mucilage cells; odor slight, distinct; taste mucilag- 
inous. 
Constituents.— The principal constituent is muci- 
lage ; it also contains starch and calcium oxalate. 
Allied Plants. — Ulmus campestris, or European elm, 
yields a bark which is dark brown, and contains, 
besides mucilage, a bitter principle and tannin. 
QUASSIA. 
The wood of Picrsena excelsa (Fam. Simarubacese), a 
tree indigenous to Jamaica. The trees are felled and 
cut into billets. The latter are exported and afterward 
manufactured into “ quassia cups,” the shavings con- 
stituting the drug of commerce. The market supply 
of this drug was at one time almost exclusively 
obtained from Quassia amara (Fam. Simarubaceie), a 
small tree indigenous to Northern South America, the 
wood being exported from Surinam and known as 
