the glands, yet according to Méhu1 only to the extent of 01 to 0.17 per cent. When distilled from the fresh strobiles the oil has a greenish colour, but a reddish-brown when old hops have been employed. We find it to be devoid of rotatory power, neutral to litmus paper, and not striking any remarkable coloration with concentrated sulphuric acid.

Griessmayer (1874) has shown that hops contain Trimethylamine, and in small proportion, a liquid volatile alkaloid not yet analysed, which he terms Lupuline. The latter is stated to have the odour of conine, and to assume a violet hue when treated with chromate of potassium and sulphuric acid.

Production and Commerce-England was estimated as having in 1873, 63,276 acres under hops. The chief district for the cultivation is the county of Kent, where in that year 39,040 acres were devoted to this plant. Hops are grown to a much smaller extent in Sussex, and in still diminished quantity in Herefordshire, Hampshire, Worcestershire and Surrey. The other counties of England, and the principality of Wales produce but a trifling amount, and Scotland none at all.

In continental Europe, hops are most largely produced in Bavaria and Wurtemberg, Belgium and France, but in each on a smaller scale than in England. France in 1872 is stated to have 9223 acres under hops.2

Notwithstanding the extensive production of hops in England, there is a large importation from other countries. The importation in 1872, was 135,965 cwt., valued at £679,276: of this quantity, Belgium supplied 66,930 cwt., Germany 36,612 cwt., Holland 16,675 cwt., the United States 10,414 cwt., France 5328 cwt. During the same period, hops were exported from the United Kingdom to the extent of 31,215 cwt.3

Uses-Hops are administered medicinally as a tonic and sedative, chiefly in the form of tincture, infusion or extract.

GLANDULE HUMULI.

Lupulina; Lupulin, Lupulinic Grains; F. Lupuline; G. Hopfendrüsen, Hopfenstaub.

Botanical Origin-Humulus Lupulus L. (see preceding article). The minute, shining, translucent glands of the strobile, constitute when detached therefrom, the substance called Lupulin.

In

History-The glands of hop were separated and chemically examined by L. A. Planche, a pharmacien of Paris, whose observations were first briefly described by Loiseleur-Deslongchamps in 1819. the following year, Dr. A. W. Ives of New York published an account of his experiments upon hops and their glands, to which latter he applied the name of Lupulin. Payen and Chevallier, Planche and others, made further experiments on the same subject, endorsing the recommendation of Ives that lupulin (or, as they preferred to call it, Lupuline) might be advantageously used in medicine in place of hops. Production-Lupulin is obtained by stripping off the bracts of hops,

1 Thèse, Montpellier, 1867. Agricultural Returns of Great Britain, &c., 1873, presented to Parliament, 48. 49. 70. 71.

3 Annual Statement of the Trade of the United Kingdom for 1872. 49. 93.

4 Manuel des Plantes usuelles et indigènes, 1819. ii. 503.

5 Silliman's Journ. of Science, ii. (1820)

302.

and shaking and rubbing them; and then separating the powder by a sieve. The powder thus detached, ought to be washed by decantation, so as to remove from it the sand or earth with which it is always contaminated; finally it should be dried, and stored in well-closed bottles. From the dried strobiles, 8 to 12 per cent. of lupulin may be obtained.

Description-Lupulin seen in quantity appears as a yellowishbrown granular powder, having an agreeable odour of hops and a bitter aromatic taste. It is gradually wetted by water, instantly by alcohol or ether, but not by potash or sulphuric acid. By trituration in a mortar, the cells are ruptured so that it may be worked into a plastic mass. Thrown into the air and then ignited, it burns with a brilliant flame like lycopodium.

Microscopic Structure-The lupulinic gland or grain, like the generality of analogous organs, is formed by an intumescence of the cuticle of the nuculæ and bracts of hop (see p. 497). Each grain is originally attached by a very short stalk, which is no longer perceptible in the drug. The gland, exhausted by ether and macerated in water, is a globular or ovoid thin-walled sac, measuring from 140 to 240 mkm. It consists of two distinct, nearly hemispherical parts; that originally provided with the stalk is built up of tabular polyhedric cells, whilst the upper hemisphere shows a continuous delicate membrane. This part therefore easily collapses, and thus exhibits a variety of form, the greater also as the grains turn pole or equator to the observer.1

The hop gland is filled with a thick, dark brown or yellowish liquid, which in the drug is contracted into one mass occupying the centre of the gland. It may be expelled in minute drops when the wall is made to burst by warming the grain in glycerin. The colouring matter, to which the wall owes its fine yellow colour, adheres more obstinately to the thinner hemisphere, and is more easily extracted from the thicker part by means of ether.

Chemical Composition-The odour of lupulinic grains resides in the essential oil, described in the previous article. The bitter principle formerly called Lupulin or Lupulite was first isolated by Lermer (1863) who called it the bitter acid of hops (Hopfenbittersäure). It crystallizes in large brittle rhombic prisms, and possesses in a high degree the peculiar bitter taste of beer, in which however it can be present only in very small proportion, it being nearly insoluble in water though easily dissolved by many other liquids. The composition of this acid, C32H5007, appears to approximate it to absinthiin; it is contained in the glands in but small proportion. Still smaller is the amount of another crystallizable constituent, regarded by Lermer as an alkaloid.

The main contents of the hop gland consist of wax (Myricylic palmitate, according to Lermer), and resins, one of which is crystalline

and unites with bases.

A good specimen of German lupulin, dried over sulphuric acid, yielded us 7.3 per cent. of ash. The same drug exhausted by boiling ether, afforded 76.82 per cent. of an extremely aromatic extract, which on exposure to the steam bath for a week, lost 3.03 per cent., this loss corre

1 For a full account of the formation of the glands, see Trécul, Annales des Sciences Nat., Bot., i. (1854) 299. An abstract may

be found in Méhu's Etude du Houblon et du Lupulin, Montpellier, 1867.

sponding to the volatile oil and acids. The residual part was soluble in glacial acetic acid and could therefore contain but very little fatty matter.

Uses The drug has the properties of hops, but with less of astringency. It is not often prescribed.

Adulteration-Lupulin is apt to contain sand, and on incineration often leaves a large amount of ash. Other extraneous matters which are not unfrequent, may be easily recognized by means of a lens. As the essential oil in lupulin is soon resinified, the latter should be preferred fresh, and should be kept excluded from the air.

ULMACEÆ.

CORTEX ULMI.

Elm Bark; F. Ecorce d'Orme; G. Ulmenrinde, Rüsterrinde. Botanical Origin-Ulmus campestris Smith, the Common Elm, a stately tree, widely diffused over Central, Southern and Eastern Europe, extending in Norway to 66° N. lat.; southward to Northern Africa and Asia Minor, and eastward as far as Amurland, Northern China, and Japan. It is probably not truly indigenous to Great Britain; but the Wych Elm, U. montana With., is certainly wild in the northern and western counties.1

History The classical writers, and especially Dioscorides, were familiar with the astringent properties of the bark of TTEλéa, by which name Ulmus campestris is understood.. Imaginary virtues are ascribed by Pliny to the bark and leaves of Ulmus. Elm bark is frequently prescribed in the English Leech Books of the 11th century, at which period a great many plants of Southern Europe had already been introduced into Britain.2 Its use is also noticed in Turner's Herbal (1568) and in Parkinson's Theater of Plants (1640), the author of the latter remarking, that "all the parts of the Elme are of much use in Physicke."

Description-Elm bark for use in medicine should be removed from the tree in early spring, deprived of its rough corky outer coat, and then dried. Thus prepared, it is found in the shops in the form of broad flattish pieces, of a rusty yellowish colour, and striated surface especially on the inner side. It is tough and fibrous, nearly inodorous, and has a woody, slightly astringent taste.

Microscopic Structure-The liber which is the only officinal part, consists of thick-walled, tangentially extended parenchyme, in which there are some larger cells filled with mucilage, while the rest contain a red-brown colouring matter. The mucilage forms a stratified deposit within the cell. Large bast-bundles arranged in irregular rows, alternate with the parenchyme and are intersected by narrow, reddish, medullary rays consisting of 2 or 3 rows of cells. The bast-bundles contain

1 On the word elm, Dr. Prior remarks that it is nearly identical in all the Germanic and Scandinavian dialects, yet does not find its root in any of them, but is an adaptation of the Latin Ulmus.-Popular Names of British Plants, ed. 2. 1870. 71.

Leechdoms, Wortcunning and Starcraft of Early England, edited by Rev. 0. Cockayne, ii (1865) pp. 53. 67. 79. 99. 127 and p. xii. In the Anglo-Saxon recipes, both Elm and Wych Elm are named.

numerous long tubes about 30 mkm. thick, with narrow cavities; and besides these, somewhat larger tubes with porous transverse walls (cribriform vessels). Each cubic cell of the neighbouring bast-parenchyme, encloses a large crystal, seldom well defined, of oxalate of calcium.

Chemistry-The chief soluble constituent of elm bark is mucilage with a small proportion of tannic acid. The concentrated decoction yields a brown precipitate with perchloride of iron; the dilute assumes a green coloration with that test. Starch is wanting, or only occurs in the middle cortical layer which is usually rejected.

Elms in summer-time frequently exude a gum which, by contact with the air, is converted into a brown insoluble mass, called Ulmin. This name has been extended to varicus decomposition-products of organic bodies, the nature and affinities of which are but little known.1

Uses-Elm bark is prescribed in decoction as a weak mucilaginous astringent, but is almost obsolete.

CORTEX ULMI FULVÆ.
Slippery Elm Bark.

Botanical Origin-Ulmus fulva Michaux, the Red or Slippery Elm, a small or middle-sized tree, seldom more than 30 to 40 feet high, growing on the banks of streams in the central and northern United States from Western New England to Wisconsin and Kentucky, and found also in Canada.

History-The Indians of North America attributed medicinal virtues to the bark of the Slippery Elm, which they used as a healing application to wounds, and in decoction as a wash for skin diseases. Bigelow writing in 1824, remarks that the mucilaginous qualities of the inner bark are well known.

Description-The Slippery Elm Bark used in medicine consists of the liber only. It forms large flat pieces, often 2 to 3 feet long by several inches broad, and usually to of an inch thick, of an extremely tough and fibrous texture. It has a light reddish-brown colour, an odour resembling that of fenugreek (which is common to the leaves also), and a simply mucilaginous taste.

In collecting the bark the tree is destroyed, and no effort is made to replace it, the wood being nearly valueless. Thus the supply is diminishing year by year, and the collectors who formerly obtained large quantities of the bark in New York and other eastern states, have now to go westward for supplies.2

Microscopic Structure-The transverse section shows a series of undulating layers of large yellowish bundles of soft liber fibres, alternating with small brown parenchymatous bands. The whole tissue is traversed by numerous narrow medullary rays, and interrupted by large intercellular mucilage-ducts. In order to examine the latter, longitudinal sections ought to be moistened with benzol, aqueous liquids causing great alteration. In a longitudinal section, the mucilage-ducts are seen to be 70 to 100 mkm. long, and to contain colourless masses of mucilage, 1 Gmelin, Chemistry, xvii. (1866) 458.

2 Proceedings of the American Pharmaceutical Association for 1873, xxi. 435.

distinctly showing a series of layers. Crystals of calcium oxalate, as well as small starch grains, are very plentiful throughout the surrounding parenchyme, but not in the mucilage-ducts.

Chemical Composition-The most interesting constituent of the bark is the mucilage, which is imparted to either cold or hot water but does not form a true solution. The bark moistened with 20 parts of water swells considerably, and becomes enveloped by a thick neutral mucilage, which is not altered either by iodine or perchloride of iron. This mucilage when diluted even with a triple volume of water, will yield only a few drops when thrown on a paper filter. The liquid which drains out is precipitable by neutral acetate of lead. By addition of absolute alcohol, the concentrated mucilage is not rendered turbid, but forms a colourless transparent fluid deposit.

Uses Slippery Elm Bark is a demulcent like althæa or linseed. The powder1 is much used in America for making poultices; it is said to preserve lard from rancidity, if the latter is melted with it and kept in contact for a short time,

EUPHORBIACEÆ.

EUPHORBIUM.

Euphorbium, Gum Euphorbium; F. Gomme-résine d'Euphorbe;
G. Euphorbium.

of

Botanical Origin-Euphorbia resinifera Berg, a leafless, glaucous, perennial plant resembling a cactus, and attaining 6 or more feet in height. Its stems are ascending, fleshy and quadrangular, each side measuring about an inch. The angles of the stem are furnished at intervals with pairs of divergent, horizontal, straight spines about an inch long, and confluent at the base into ovate, subtriangular discs. These spines represent stipules: above each pair of them is a depression, indicating a leaf-bud. The inflorescence is arranged at the summits of the branches, on stalks each bearing three flowers, the two outer of which are supported on pedicels. The fruit is tricoccous, of an inch wide, with each carpel slightly compressed and keeled.

The plant is a native of Morocco, growing on the lower slopes of the Atlas in the southern province of Suse. Dr. Hooker and his fellow travellers met with it in 1870, at Imsfuia, south-east of the city of Morocco, which appears to be its westward limit.

History-Euphorbium was known to the ancients. Dioscorides and Pliny both describe its collection on Mount Atlas in Africa, and notice its extreme acridity. According to the latter writer, the drug received its name in honour of Euphorbus, physician to Juba II., king of Mauritania. This monarch, who after a long reign died about A.D. 18, was distinguished for his literary attainments, and was the author of several books which included treatises on opium and euphorbium. The latter work was apparently extant in the time of Pliny.

Euphorbium is mentioned by numerous other early writers on medi3 Lib. v. c. 1; lib. xxv. c. 38.

1 That sold in America is sometimes adulterated with farinaceous substances.

2 Lib. iii. c. 86.

Smith, Dict. of Greek and Roman Biography, ii. (1846) 636.