LACTUCA VIROSA. STRONG-SCENTED LETTUCE. 
Class XIX. SYNGENESIA. Order I. POLYGAMIA. 
Natural Order, CICHORACEHL. 
Fig. (a) represents a floret with the five united anthers, somewhat magnified; (6) a single akenopsis with the pappus. 
This is a biennial plant; a native of Britain, and other parts of Europe: occurring chiefly in dry warm 
hedges, and waste grounds, where the soil is calcareous. We perceived it (says Professor Burnett,) in the 
hedges about Kilburn, on the road to Harrow ; in Maiden-lane, near Copenhagen House ; at Kingston- 
bottom, near Coombe Wood, Surrey, and other places near London. 
The stem is somewhat woody, rising from two to six feet high; it is erect, slender, very slightly prickly 
below, smooth above, round, panicled, and thinly clothed with leaves. The leaves are alternate, glabrous, 
toothed, undivided at the base, and spreading ; the cauline ones amplexicaul, sinuate, sometimes lobed, with 
the midrib armed with short spines on the under side. The bracteas, or floral leaves, are cordate, and 
pointed. The flowers which expand only in bright sunny mornings, are small, compounded, of a sulphur^ 
yellow colour, and appear in terminal panicles, in August and September. The involucre or calyx is nearly 
cylindrical, and composed of numerous pointed, imbricated, unequal, flat scales, with membranous edges. 
The inflorescence is compound, imbricated, and uniform ; the florets numerous, perfect, equal, monope- 
talous, ligulate, truncated, and four or five-toothed. There are five very short capillary filaments, having 
the anthers united into a cylindrical tube. The germen is nearly ovate, supporting a slender style, longer 
than the stamens, with two reflexed stigmas. The fruit is an obovate akenium or rather akenopsis sur- 
mounted with the stipitate pappus, which is fugacious. The seeds are solitary, erect, and exalbuminous : 
with the radicle taper and inferior. 
The systematic name, Lactuca, from lac, milk, is obviously expressive of the milky juice with which 
the plants of this genus generally abound. Virosa, poisonous, the trivial name, alludes, no doubt, to its 
acrid and deleterious properties. 
The leaves and stem of this plant abound with a milky juice, which may be collected in great abun- 
dance, just as it is beginning to flower: in the same manner as that recommended by Mr. Jeston, of Henly- 
upon-Thames, for English opium. Sir J. Hill recommends it to be practised in the month of April, which 
is certainly too early: and Dr. Todd Thomson says that the plant must be gathered, and the juice expressed; 
a plan we consider to be objectionable, as the other fluids must necessarily be mixed with the white juice : 
which is of a strong fetid smell, of a bitter and acrid taste, and possesses the active powers of the plant. 
Poisonous Effects. — Two drachms of the watery extract were applied, by M. Orfila, to the cellular 
texture of the back of a dog. At the end of two days, the animal, who had only been slightly drowsy, had 
some vertigoes, and died seventy hours after the operation. The ventricles of the brain contained no fluid; 
the exterior veins of that organ were distended and injected with black blood ; the lungs presented a few 
patches of a brownish red colour, and their texture was somewhat more dense than natural. 
In a dog (says Professor Burnett,) which had been poisoned by three drachms of the extract, introduced 
in the stomach, dissection of the body threw no light on the cause of his death : and in a rabbit which died 
a short time after we had administered half an ounce of the expressed juice, in a fluid state, we could dis- 
cover no morbid appearances whatever. 
We consider this (observes Mr. Burnett,) as one of the most valuable of our native plants: the inspis- 
sated juice is a mild sedative, and if administered in proper doses, constitutes an excellent substitute for 
opium ; when its diuretic effects, which are somewhat powerful, are not contra-indicated. It generally proves 
somewhat laxative ; promotes gentle perspiration, and allays thirst. By the Germans its virtues are highly 
extolled, and they administer it in palpitation of the heart, and in intermittent fever. Dr. Collin relates 
twenty-four cases of dropsy ; twenty-three of which were cured by taking it, in doses of eighteen grains, to 
three drachms, every twenty-four hours. In a dropsical case, that lately came under our care, it certainly 
produced a salutary action on the kidneys, and procured quiet sleep. We have also ascertained, to our own 
satisfaction, that it possesses another most important virtue, viz. that of reducing the velocity of the pulse; 
at the same time that it appears to increase its tone: and so remarkably efficient was its action on one 
patient, that three small doses of the tincture diminished the arterial impetus in the wrist from one hundred 
and twenty pulsations in the minute, to less than seventy ; accompanied by intermissions. 
