38 
LACTUCA VIROSA. 
and about old walls. The stem of this plant is straight, covered 
with scattered prickles, and seldom exceeds two feet in height; 
towards the superior part it is furnished with a few branches, which 
are alternate and slender ; the inferior leaves are oblong, amplexical, 
auriculated at the base, sometimes lobed, unequally dentated and 
thorny on their upper side ; the superior are arrow-shaped and entire, 
the midrib armed with short spines on the under side ; the bracteas 
are cordate and pointed ; the calyx is oblong, pointed, and nearly 
cylindrical, imbricated, and formed of straight, elongated, pointed, 
unequal scales, membraneous on the edges ; the flowers are com- 
pound, disposed in small clusters; the florets are monopetalous, 
hermaphrodite, ligulated, and dentated ; the filaments are five, anthers 
united into a cylindrical tube ; the germen ovate, style slender, the 
length of the stamen ; stigmata, two and reflected ; seeds oblong, 
compressed, striated, of a dark brown, and crowned by a soft, 
fleeting pappus. 
Every part of this plant contains a viscid, bitter, milky juice, of a 
very disagreeable smell. In this juice its sensible qualities seem to 
reside. Dioscorides describes the odour and taste of the juice as 
nearly agreeing with that of the white poppy, and its effect, according 
to Haller, are powerfully narcotic ; from recent analysis, it is found 
to contain an alkali analogous to morphia, and on which no doubt 
its active properties depend. 
Action of the Strong Scented Lettuce on the Ani- 
mal Economy. The strong scented lettuce has been ranked 
among the narcotic poisons ; but from the experiments of Orfila and 
others, the fresh plant does not seem to be possessed of active 
properties.* The extract prepared by evaporating the expressed 
juice, possesses more energetic properties ; and in doses of from one 
to two drachms, invariably proved fatal to dogs, when introduced 
into the stomach, injected into the jugular vein, or even applied to 
the cellular texture. f 
The general symptoms produced were, eflx>rts to vomit, vertigo, 
slight convulsive movement, great drowsiness, followed by death. 
Dissection threw no particular light on the cause of death. The 
alimentary canal scarcely shewed any appearance of inflammation, 
and the sanguiferous system presented the usual appearance as in 
* A strong dog was made to swallow oue pound and a half of the fresh leaves of the 
sirong scented lettuce, without experiencing the least inconvenience. 
Orfila, vol. ii. p. 15^. 
+ "^'ide Orfila on Poisons, vol. ii, p. 160. 
