In the Brazilian forests, the plant, there known as poaya, is found growing in clumps, under the dense shade of old trees. It is collected by grasping all the stems of a clump, and raising the mess by the help of a pointed stick, inserted beneath the roots and worked up and down to loosen the soil ; the object is to got up the whole network of roots unbroken. The adhering earth is then shaken off, and the roots are thrust into a bag. Sometimes 30 lb. are thus collected by one man in n day ; but the average does not exceed 10-12 lb., and some do not get more than 6-8 lb. The gatherers or poayeros assemble in the evening to weigh their gleanings, and spread them out to dry. Rapidity is desirable in this operation ; the roots are exposed to the sun, and should become dry in 2-3 days, being housed at night to avoid the dew. After drying, they are broken up, the adherent earthy matters are sifted away from them, and the drug is packed in bales. The collecting is suspended only during the rains, when drying would be difficult ; moderately damp weather, how ever, is beneficial, as assisting in the uprooting of the plant. To prevent extirpation of the plant, small fragments of the root are loft in the ground, and covered over. The commercial drug is never thicker than in. and generally much less ; its colour is dusky greyish-brown ; its flavour is bitterish ; its odour, faint and musty. The roots are hard and brittle; they always arrive much broken, and are frequently mouldy, and damaged by sea-water. The drug is imported in serene made of cowhide. The stem is often mixed with the root in considerable quantity. Such samples are inferior, as the activity resides in the bark, which, in the stem, is very thin. Our imports of the drug in 1870 (the last detailed return) were nearly 63,000 lb.
Owing to the monopoly of the collection, and the exhaustion of the most accessible ground, the wholesale price of the drug rose from 2s. 9id. a lb. in 1850, to 8s. 8d. in 1870 ; it has since fallen from about 5s. 6d.-5s. 9d. in 1878, to 4s. 3d.-48. 6d. in 1879.
Besides the Brazilian drug, another variety, called " Carthagena,'" or "New Granada," has, of recent years, been imported into London. It is a little less active than the ordinary drug, and differs from it principally in attaining a greater size in.).
A few worthless roots are occasionally put upon the market under the pseudonym of the true drug. They are chiefly:—(l) "Large striated ipecacuanha," the root of Psychotria emetics, indi genous to Colombia ; may be known by its remaining moist and tough, even for years, and by being larger than the true drug, and not annulated. (2) " Small striated,' probably from a species of .Ricliardsotaa ; closely resembles the first, except in size. (3) " White " or "undulated," the root of Richardia (Richardsonia) seabra, exceedingly common in Brazil; it is paler than ipecacuanha, fissured on alternate sides, but not furnished with raised rings as in the true drug. (4) "False Brazilian," the root of Ionidium Ipecacuanha, a plant of the order Violacece. It is called in Brazil Poaya blanca. The root is dirty-white, branched, much longer and less brittle than the true drug, and not annulated. It has repeatedly been offered in the London drug sales of late years. (5) In Mauritius, the leaves and root of Tylcphora asthmatica are used as a substitute for ipecacuanha, under the name of ipeta sauvage, or ipeca du pays. In India, the same plant is used, and is known as
"country," or "Indian " ipecacuanha.
Iridin.—This is a cholagogue principle, extracted from the root of Iris versicolor, much used in the United States, and to a certain extent in this country. The root is reddish internally, and has no odour.
Irish Moss, or Carrageen (FE., Mousse d'Irlande [perlee]; GER., Knorpeltang, Irlandisches [Peri] Moos).—Carrageen, or more properly Carraigeen, is the seaweed Chondrus (Fucus) crispus, used in the form of jelly for consumptive patients. The plant is distributed along the rocky shores of Europe, from Gibraltar to the N. Cape ; but is wanting in the Mediterranean, and infre quent in the Baltic. On the E. coast of N. America, it is abundant. The districts yielding the commercial weed are, however, very limited. It is gathered on the W. and N.W. coasts of Ireland, to be despatched from Sligo, and parcels of a good quality come occasionally from Hamburg ; but the principal supply is sent from Boston, U.S. Though the plant is widely scattered along the coast of Massachusetts and other States, it is very generally infested with mussels and various minute mollusca, which circumstance unfits it for use. The gathering, or " mossing," is therefore confined to the rocks within a few miles of the Minot Ledge Lighthouse, Scituate, Plymouth County, Mass., where it forms a distinct industry. The " pull " begins late in the spring tide of the full moon of May, and lasts till early September. Previously, the " bleaching-beds " are prepared, by raking the stones off sandy plots on the beach. The rocks are reached in boats, the spring tides being chosen on account of the large space uncovered by the ebb of the tide at this season. The best growth is hand-pulled, with great care to ensure its freedom from shells and tape-grass ; when properly cured, it fetches 2-3 times as much as the bulk of the crop, and is the only kind supplied to druggists. When the tide guards the best ledges, recourse is had to a long-handled iron rake, with which the plentiful commoner growths are torn from the submerged rocks. These are never free from weeds and shells ; but, nevertheless, they form excellent material for the manufacture of size. The contents of the laden boats are spread to dry on the bleaching-beds, and then undergo repeated washing (in salt water), and drying, till sufficiently white. In fine weather, 6 washings will generally suffice ; wet weather is fatal to the quality of the article, indeed it rapidly dissolves in fresh water. When cured, it is stored in shanties till the harvest is done, and is then picked over, and packed in barrels, about 100 lb. in each. The crop improves in quality, and increases in quantity, by repeated pulling. The annual harvest amounts to about + million lb. The second quality is largely used for fining beer ; while lower grades find an application in the sizing of cottons and paper, and in the stuffing of mattresses. In this country, it is sometimes used for feeding cattle. The commercial article frequently contains other seaweeds, as Gigartina mammillosa (Chondrus mammillosus), and G. acicularis.