_Radix Scillæ_; _Squill_; F. _Bulbe ou squames de Scille_, _Ognon
marin_; G. _Meerzwiebel_.
=Botanical Origin=—_Urginea maritima_ Baker[2582] (_Scilla maritima_
L., _Urginea Scilla_ Steinheil). It is found generally in the regions
bordering the Mediterranean, as in Southern France, Italy, Dalmatia,
Greece, Asia Minor, Syria, North Africa and the Mediterranean islands.
In Sicily, where it grows most abundantly, Urginea ascends to
elevations of 3000 feet. It is also very common throughout the South of
Spain, where it is by no means confined to the coast; it occurs also in
Portugal. In the Riviera of Genoa the peasants like to see it growing
under the fig trees.
Two varieties of squill, termed respectively _white_ and _red_,
are distinguished by druggists. In the first, the bulb-scales are
colourless; in the second they are of a roseate hue. No other
difference in the plants can be pointed out, nor have the two varieties
distinct areas of growth.
=History=—Squill is one of the most ancient of medicines. Epimenides,
a Greek who lived in the 30th Olympiad, is said to have made much use
of it, from which circumstance it came to be called _Epimenidea_[2583].
It is also mentioned by Theophrastus, and was probably well known
to all the ancient Greek physicians. Pliny was not only acquainted
with it, but had noticed its two varieties. Dioscorides describes the
method of making vinegar of squills; and a similar preparation, as well
as compounds of squill with honey, were administered by the Arabian
physicians, and still remain in use. The medical school of Salerno
preferred the red variety of the drug, which on the whole is not
frequently met with in mediæval literature.
[2581] By R. V. Tuson, London, 1869.
[2582] _Journ. of Linn. Soc._, Bot., xiii. (1872) 221.—The genus
_Urginea_ has flat, discoid seeds, while in _Scilla_ proper they are
triquetrous. The name _Urginea_ was given in allusion to the Algerian
tribe Ben _Urgin_, near Bona, where Steinheil (1834) examined this
plant.
[2583] Haller, _Bibliotheca botanica_, i. 12.
=Description=—The bulb of squill is pear-shaped, and of the size of
a man’s fist or larger, often weighing more than four pounds. It
has the usual structure of a tunicated bulb; its outer scales are
reddish-brown, dry, scarious, and marked with parallel veins. The inner
are fleshy and juicy, colourless or of a pale rose tint, thick towards
the middle, very thin and delicate at the edges, smooth and shining on
the surface. The fresh bulb has a mucilaginous, bitter, acrid taste,
but not much odour.
For medicinal use, squill is mostly imported ready dried. The bulbs are
collected in the month of August, at which period they are leafless,
freed from their dry outer scales, cut transversely into thin slices,
and dried in the sun. Thus prepared, the drug appears in the form of
narrow, flattish or four-sided curved strips, 1 to 2 inches long, and ⅜
to ⅝ of an inch wide, flexible, translucent, of a pale dull yellowish
colour, or when derived from the red variety, of a decided roseate
hue. When thoroughly dried, they become brittle and pulverizable, but
readily absorb water to the extent of about 11 per cent. Powdered
squill by the absorption of water from the air, readily cakes together
into a hard mass.
=Microscopic Structure=—The officinal portion of the plant being simply
modified leaves, has the histological characters proper to many of
those organs. The tissue is made up of polyhedral cells, covered on
both sides of the scales by an epidermis provided with stomata. It
is traversed by numerous vascular bundles, and also exhibits smaller
bundles of laticiferous vessels. If thin slices of squill be moistened
with dilute alcohol, most of the parenchymatous cells are seen to be
loaded with _mucilage_, which contracts into a jelly on the addition of
alcohol. In the interior of this jelly, crystalline particles are met
with consisting of oxalate of calcium. This salt is largely deposited
in cells, forming either bundles of needle-shaped crystals, or large
solitary square prisms, frequently a millimetre long. In either case
they are enveloped by the mucilaginous matter already mentioned.
Oxalate of calcium as occurring in other plants has been shown in many
instances to originate in the midst of mucilaginous matter. The fact is
remarkably evident in _Scilla_, especially when examined in polarized
light.
On shaking thin slices of the bulb with water, the crystals are
deposited in sufficient quantity to become visible to the naked eye,
though their weight is actually very small. Direct estimation of the
oxalic acid (by titration with chamæleon solution) gave us only 3·07
per cent. of C₂CaO₄,3H₂O from white squill dried at 100° C., which
moreover yielded only 2 to 5 per cent. of ash. It is these extremely
sharp brittle crystals which occasion the itching and redness, and
sometimes even vesication, which result from rubbing a slice of fresh
squill on the skin. These effects, which have long been known, were
attributed to a volatile acrid principle, until their true cause was
recognized by Schroff.[2584]
[2584] We have found that the slimy juice of the leaves of _Agapanthus
umbellatus_ Hérit., which is very rich in spicular crystals, also
occasions when rubbed on the skin both itching and redness, lasting for
several hours.
The mucilage also contains albuminous matters, hence the orange colour
it assumes on addition of iodine. The vascular bundles are accompanied
by some rows of longitudinally extended cells, containing a small
number of starch granules. In the red squill the colouring matter is
contained in many of the parenchymatous cells, others being entirely
devoid of it. It turns blackish-green if a persalt of iron be added.
=Chemical Composition=—The most abundant among the constituents of
squill are mucilaginous and saccharine matters. Mucilage may be
precipitated by means of neutral and basic acetate of lead, yet there
remains in solution another substance of the same class, called
_Sinistrin_. It was discovered in 1879 by Schmiedeberg, who obtained it
by mixing the powder of squill, either red or white, with a solution of
basic acetate of lead in slight excess. The gummy matters thus forming
insoluble lead compounds being removed, the liquid is deprived of the
lead and mixed with slaked lime. An insoluble compound of sinistrin
and calcium separates and yields the former on decomposing the well
washed precipitate with carbonic acid. The small amount of calcium
remaining in the filtrate is to be removed by adding cautiously to the
warm solution the small quantity just required of oxalic acid. Lastly,
sinistrin is thrown down by alcohol. It is a white amorphous powder, on
exposure to air soon forming transparent brittle lumps. The composition
of sinistrin is that of dextrin = C₆H₁₀O₅, both these substances being
very closely allied, yet the aqueous solution of sinistrin deviates the
plane of polarization to the left. The rotatory power appears not to be
much influenced by the concentration or the temperature of the solution
of sinistrin.
An alkaline solution of tartrate of copper is not acted upon by
sinistrin. It is transformed into sugar by boiling it for half an hour
with water containing 1 per cent. of sulphuric acid. The sugar thus
produced is stated by Schmiedeberg to consist of lævulose[2585] and
another sugar, which in all probability, when perfectly pure, must
prove devoid of rotatory power.
The name sinistrin[2586] has also been applied to a mucilaginous matter
extracted from barley (see Hordeum decorticatum); it remains to be
proved that the latter is identical with the sinistrin of squill.
We have obtained a considerable amount of an uncrystallizable levogyre
sugar by exhausting squill with dilute alcohol.[2587] Alcohol added to
an aqueous infusion of squill causes the separation of the mucilage,
together with albuminoid matter. If the alcohol is evaporated and
a solution of tannic acid is added, the latter will combine with
the _bitter principle_ of squill, which has not yet been isolated,
although several chemists have devoted to it their investigations,
and applied to it the names of _Scillitin_ or _Skuleïn_. Schroff, to
whom we are indebted for a valuable monograph on Squill,[2588] infers
from his physiological experiments the presence of a non-volatile
acrid principle (_Skulein?_), together with scillitin, which latter he
supposes to be a glucoside.
Merck of Darmstadt has isolated _Scillipicrin_, soluble in water;
_Scillitoxin_, likewise a bitter principle, insoluble in water, but
readily dissolving in alcohol; and _Scillin_, a crystalline substance,
abundantly soluble in boiling ether. The physiological action of these
substances and of _Scillaïn_ has been examined (1878) by Moeller, and
by Jarmersted (1879); that of scillitoxin and scillaïn was found to be
analogous to that of Digitalis.
[2585] This is the name applied to the lævogyrate uncrystallizable
glucose produced, together with crystallizable dextro-glucose, by
decomposing cane-sugar by means of dilute acids.
[2586] In 1834 first proposed, by Marquart, for inulin.
[2587] In Greece they have even attempted to manufacture alcohol by
fermenting and distilling squill bulbs.—Heldreich, _Nutzpflanzen
Griechenlands_, 1862. 7.
[2588] Reprinted from the _Zeitschrift der Gesellschaft der Aerzte zu
Wien_, No. 42 (1864). Abstracted also in Canstatt’s _Jahresbericht_
1864. 19, and 1865. 238.
=Commerce=—Dried squill, usually packed in casks, is imported into
England from Malta.
=Use=—Commonly employed as a diuretic and expectorant.
=Substitutes=—There are several plants of which the bulbs are used in
the place of the officinal squill, but which, owing to the abundance
and low price of the latter, never appear in the European market.
1. _Urginea altissima_ Baker (_Ornithogalum altissimum_ L.), a South
African species, very closely related to the common squill, and having,
as it would appear, exactly the same properties.[2589]
2. _U. indica_ Kth. (_Scilla indica_ Roxb.), a widely diffused plant,
occurring in Northern India, the Coromandel Coast, Abyssinia, Nubia,
and Senegambia. It is known by the same Arabic and Persian names as _U.
maritima_, and its bulb is used for similar purposes. But according to
Moodeen Sheriff[2590] it is a poor substitute for the latter, having
little or no action when it is old and large.
3. _Scilla indica_ Baker[2591] (non Roxb.), (_Ledebouria hyacinthina_
Roth), native of India and Abyssinia, has a bulb which is often
confused in the Indian bazaars with the preceding, but is easily
distinguishable when entire by being _scaly_ (not tunicated); it is
said to be a better representative of the European squill.[2592]
4. _Drimia ciliaris_ Jacq., a plant of the Cape of Good Hope, of the
order _Liliaceæ_. Its bulb much resembles the officinal squill, but has
a juice so irritating if it comes in contact with the skin, that the
plant is called by the colonists _Jeukbol_, i.e. _Itch-bulb_. It is
used medicinally as an emetic, expectorant, and diuretic.[2593]
5. _Crinum asiaticum_ var. _toxicarium_ Herbert (_C. toxicarium_
Roxb.), a large plant, with handsome white flowers and noble foliage,
cultivated in Indian gardens, and also found wild in low humid spots
in various parts of India and the Moluccas, and on the sea-coast of
Ceylon. The bulb has been admitted to the _Pharmacopœia of India_
(1868), chiefly on the recommendation of O’Shaughnessy, who considers
it a valuable emetic. We have not been able to examine a specimen,
and cannot learn that the drug has been the subject of any chemical
investigation.
[2589] Pappe, _Floræ Medicæ Capensis Prodromus_, ed. 2, 1857. 41.
[2590] _Supplement to the Pharmacopœia of India_, Madras, 1869. 250.
[2591] Saunders, _Refugium Botanicum_, iii. (1870) appendix, p. 12.
[2592] _Suppl. to the Pharm. of India_, 250.
[2593] Pappe, _op. cit._ 42.