are several separate cysts. They often attain a considerable size. Rokitansky mentions one in the Vienna Museum of a foot in diameter, and we have very recently examined one of an oval form, whose long diameter measured six inches. Their usual site is the right lobe, and the largest are generally found here, but the one just mentioned was situated at the extremity of the left, and had grown in, and far beyond, the left lateral ligament. As their size increases, they rise to the surface of the liver, and sometimes excite inflammation of the serous membrane, by which adhesions are formed connecting them with the parts adjacent. The prominent part is, of course, that where least resistance is offered to the pressure of the fluid within, and its wall may hence atrophy and give way, or be destroyed in the course of suppurative inflammation, and the contents thus be effused into some neighboring cavity. The cysts have been known to burst into the peritoneal sac, into that of the right pleura, or into the bronchi of the corresponding lung, into the duodenum or transverse colon, and in some rare instances, into a large blood vessel or branch of the hepatic duct. When the tumor, in its progress, causes ulceration of one of the smaller ducts, which is not uncommon, bile makes its way into the cavity, mingles with and tinges its contents, and very often excites suppurative inflammation of the walls of the sac. This seems to be the reason that hydatid tumors in the liver suppurate much more frequently than those in other parts. Other circumstances, however, may certainly cause these cysts to inflame and suppurate. The detailed description of the structure of hydatid cysts will be found under the head of Parasites, p. 218; it will, therefore, be sufficient to mention here that they possess an outer wall or envelop, formed of condensed areolar tissue and that of the surrounding structure; within which, and rather loosely adhering to it, is the proper membrane. This is white and laminated, and is itself lined internally by a softish layer in which the echinococci are developed. The cavity of the primary cyst is occupied in some instances by a transparent limpid fluid only; in others, and the majority, it also contains a numerous progeny of secondary cysts, which may themselves contain another generation. Dr. Budd mentions the interesting fact, that in cases where suppuration has occurred in the cavity of the primary cyst, the secondary hydatids, though floating in purulent matter themselves, contain a perfectly limpid fluid. He also points out characters whereby to distinguish between an abscess and a suppurated hydatid cyst, in the differences which the cystic membranes in the two cases present. That of an abscess consists of dense fibroid tissue, is not laminated, and never contains calcareous matter. The hydatid membrane does not adhere so firmly to the surrounding tissue, is markedly laminated, and in old cases contains very often plates or grains of calcareous matter in its coats. When an hydatid tumor has evacuated its contents as above described,

1 Some doubt may exist whether the purulent-looking fluid contained in the cyst is always true pus. In a case occurring at St. Mary's Hospital, the matter from the interior of a large cyst, which had to the naked eye all the appearance of pus, was found under the microscope to consist of much granular and oily matter, with some cholesterin, and numerous utterly irregular granular masses. There were no true pus-glo

bules.

it may collapse and a cure be effected; but if its walls are very thick and firm, and the cavity large, its obliteration in this way may be impossible, and thence there is too much reason to fear that, owing to the entrance of air or other matters, suppurative inflammation of the sac will be excited, and the drain exhaust the strength of the patient. But an hydatid cyst may come to a spontaneous cure in a different way; its proper membrane, instead of secreting a watery fluid may produce a putty-like matter, consisting of phosphate and some carbonate of lime, with cholesterin and albuminoid matter. This accumulates within the sac, or sometimes around it, imbeds the secondary hydatids, and causes them to shrivel up and perish. Such a change reminds one forcibly of the cretification of tubercle, which is often observed in cases where the tubercular dyscrasia has ceased, and the deposited matter has been partially absorbed. Hydatids in the liver are not unfrequently associated with hydatids in other parts, in the lower lobes of the lungs, or in the spleen, or in the mesentery; in such cases, Dr. Budd is inclined to regard. the hepatic cyst as the parent, and the others as originated from germs conveyed from it. The arguments which support this view are, the greater apparent age of the hepatic cyst, and the circumstance that the one "in the liver is associated only with cysts in the lung or in the mesentery;" this seems to indicate rather that the one is derived from the other, than that both are of independent origin. It is also to be remarked that an hydatid cyst often occurs in the liver alone, but rarely, if ever, alone in the spleen or mesentery. These arguments are, certainly, of weight, but seem hardly sufficient to counterbalance the objections, that it is difficult to conceive how a germ from the hepatic cyst should make its way backwards against the stream of blood to the spleen or the mesentery, and that it cannot be considered improbable that a second hydatid should originate in a different locality, in a system which has already shown itself favorable to the production of a primary one.

Cancerous disease is very frequent in the liver: it stands fourth in the list of organs thus affected, according to the Parisian registers; these show that it occurs about once in every sixteen cases of cancer: Rokitansky estimates its occurrence in the liver to be much more frequent; he states "its numerical relation to carcinoma of other organs, as 1: 5." The above statements do not, of course, refer to primary cancer of the liver only, but include secondary cancer also. Three varieties of cancer have been observed in the liver; colloid is extremely rare, neither Dr. Budd nor Dr. Walsh has met with it; Rokitansky seems only to have seen a single case, and he does not state whether it was primary or secondary. Scirrhus is not very unfrequent, or a transition variety between it and encephaloid: it constitutes roundish tumors, about the size of a large nut, whitish, fibrous, and tolerably firm. Encephaloid is far the most common, and, as in other parts, attains far the largest size. We have seen almost the whole organ converted into a mass of this kind. It sometimes forms separate tumors, sometimes infiltrates the parenchyma. Rokitansky's description of the separate tumors seems to us to apply equally to the scirrhous and encephaloid varieties, as he himself appears to allow. He says: "Their general

form is spherical, though their surface not unfrequently is slightly racemose or lobulated. Those which have been developed in the peripheral portion of the organ, and are, therefore, in contact with the peritoneum, present a flattened or even an indented surface, and the indentation may extend to the very nucleus of the morbid growth. The peritoneal lamina in the indentation is opaque and thickened," probably from having become involved in the cancerous degeneration; it seems to be retracted and drawn in much the same way as the skin is in subcutaneous cancer. The number of the cancerous tumors varies in different cases; they may be solitary or very numerous; primary cancers are usually few, secondary may amount to some hundreds. Dr. Walsh thinks they are most numerous when they occur consecutively to cancer of the

"Infil

stomach. The scirrhous tumors have scarce any investments of cellular tissue, and adhere closely to the surrounding hepatic parenchyma; the encephaloid have a delicate cyst-like investment, though this does not seem to be constant, and they can be detached more readily. trated encephaloid," according to Rokitansky, "always contains obliterated and obsolete blood vessels, and ducts which are gradually absorbed. The infiltration attacks larger or smaller segments of the viscus; it does not present distinct boundaries, but insensibly passes into the normal parenchyma. It rarely occurs without nodulated cancer." The separate tumors often inclose strata of remaining hepatic structure, a fact which seems to mark a connection between the two forms; some degree of infiltration taking place in each; but in one, the growth simply pushes the parenchyma aside, in the other it spreads its germs everywhere among its elements. The structure of cancerous tumors presents nothing different from that of cancerous tumors in other parts, and is described under the general head of cancer (p. 187). Their degree of vascularity varies: some tumors show very little trace of blood vessels, others are richly supplied, and are the seat also of interstitial effusions

of blood; to such, the term hæmatoid or fungus hæmatodes is appropriate. Black pigment often is scattered through the substance of the growths, and may be so abundant as to make them appear entirely black. These claim, of course, the appellation melanotic.

Cancerous tumors in most cases produce considerable enlargement of the liver, the atrophy of the proper tissue which they occasion being more than compensated by the amount of their own enlargement; in some rare cases, however, this does not take place, and the liver, though containing many cancerous tumors, is smaller than natural. Masses of cancer which appear on the surface of the liver, sometimes excite adhesive inflammation of the investing serous membrane, and thus become united by false membrane to adjacent parts. Instead of this, they have been known to infect with their tainted fluids the parts in contact with them, and to cause secondary formations of cancer in them, or to extend into them, by the ordinary way of infiltration. Ascites, to some extent, is not unfrequently produced by the presence of cancerous masses in the liver: this probably depends on the obstruction of the portal veinbranches, either by the tumors themselves, or by cancerous matter developing in them, or by fibrinous effusion coagulated within their channel. Jaundice is often observed in cancerous disease of the liver; its production, doubtless, takes place in the same way as that just noticed; the gall-ducts being obstructed, and the escape of bile from various parts of the organ prevented. When the masses are so situated as to press on the common duct leaving the others free, enormous distension of the gall-bladder may take place-it has been seen as large as the foetal head; such a result, however, is more likely to be produced by cancerous disease of the head of the pancreas, than by growths in the substance of the liver. Primary cancer of the liver is stated by Dr. Budd, seldom, if ever, to occur before the age of 35: from this to 55 is the epoch at which it most frequently manifests itself. Secondary cancers of the liver may occur at any age: they seem, according to Dr. Walsh, to affect a preference for the superficial parts of the organ. They are believed to be produced by the transportation of germs in the blood, or by the medium of the lymphatics; this, doubtless, is often true, but we certainly are of opinion that fluid cancerous blastema is quite as adequate to their production as any solid particle, and this cannot but be absorbed by blood passing through a malignant tumor. There seems evidence to show that when the part primarily affected returns its blood to the liver directly, as in the case of cancer of the stomach, the infectious matter is all detained there, and tumors are not formed in other parts; but when hepatic cancer is consecutive to cancer of the breast, its development must then depend on the absorbed matter finding a suitable nidus in that organ. A sort of spontaneous cure of hepatic carcinoma has been occasionally observed, the morbid growth becoming converted into a fatty mass, doubtless by a change of the nature of fatty degeneration.

ABNORMAL CONDITIONS OF THE BILIARY PASSAGES.

Malformations. The gall-bladder is sometimes wanting-in animals it has been found double; its shape may be variously deformed; its duct, as well as the common duct, may probably be imperforate. The cystic and hepatic duct may remain separate, and communicate either both with the duodenum, or one with the duodenum and the other with the stomach. The mucous lining of the gall-bladder and ducts is often attacked with inflammation, which may extend from the duodenum, and spread upwards along the ducts. It is often of the catarrhal kind, and is essentially similar to the affection of the gastro-intestinal mucous surface; like it, subsiding after a time, and leaving no traces of its existence behind. The effects it produces will be those of vascular injection, some degree of tumefaction, shedding to a greater or less extent of the epithelium, and casting off of mucous corpuscles and various forms of immature epithelia, together with exudation of liquor muci, of various degrees of viscidity and tenacity. The gall-bladder alone may be the seat of acute idiopathic inflammation, or this may be excited by unhealthy bile, or, perhaps, by the irritation of a calculus. The result of such inflammation may be closure of the cystic duct, and conversion of the gall-bladder into an abscess. If the catarrhal inflammation, or that set up in any other way, attain a certain degree of intensity, it causes the effusion of muco-purulent or purulent matter, and at the same time it seems to induce paralysis of the contractile coat of the biliary ducts; these tubes, thus weakened, yield to the distending force within of the accumulating secretion, and become dilated at intervals into cyst-like pouches, filled with muco-pus tinged yellow or green by bile. The dilatation will, of course, be promoted, if the common duct, or the hepatic, is obstructed by a calculus, or in any other way. After such pouches have existed a certain time, they become entirely cut off from the duct in which they originated, the tube becoming obliterated by adhesion, and their contents then undergoing certain changes. Thus, the muco-purulent matter may be converted into a clear glairy fluid, more or less tinged with bile; we have recently observed a case of this kind, and though we were some time in doubt as to the nature of the cyst, which was found in a healthy liver, we were soon convinced by detecting particles of columnar epithelium in the matter lining its surface; besides the fluid in this case, there were several small whitish masses attached to the inner surface, consisting of a semi-homogeneous, semi-granulous, soft substance, containing imperfect celloid forms. seems probable that, had the person survived longer, these whitish masses. would have increased considerably, so much as to fill the cyst, and that in this way one of those peculiar tumors would have been produced which Dr. Budd has called "knotty tumors of the liver," and which he believes. to be formed within the ramifications of the hepatic ducts. He describes them as firm, white nodules, surrounded by a distinct cyst, and containing a cheese-like substance, in the centre of which is a small mass of concrete biliary matter; they are evidently situated in portal canals, and have often been mistaken for cancerous tumors. We think it is too