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XXXIV] the cavity. Though the pus and detritus lying on the abscess wall are viscid and adhesive, there is no notable exudation of lymph either lining the cavity or in the still living liver tissue beyond. There is a peripheral zone of hyperæmia; beyond this zone the gland may appear normal or simply congested. Number, size, and situation of abscesses.— Liver abscess may be single or multiple. If multiple, there may be two, three, or many abscesses. Zancarol's statistics, applying to 562 cases, give the proportion of single to multiple abscess cases as three of the former to two of the latter.

When single the abscess sometimes attains a great size. Frequently it is as large as a coco-nut or even larger; it has happened that the entire liver, with the exception of a narrow zone of hepatic tissue, has been converted into a huge abscess sac. When multiple the individual abscesses are generally smaller, ranging in size from a filbert to an orange. As might be expected from considerations of the relative size of the parts, single abscess is much more common in the right than in the left and smaller lobes. What might be termed the seat of election is the upper part of the right lobe. Roux gives the proportions in 639 cases as 70-85 per cent, right lobe, 3 per cent, left lobe, and 0.3 per cent, lobus Spigelii.

Adhesions to surrounding organs are frequently, though not invariably, formed as the abscess approaches the surface of the liver. In this way the danger of intraperitoneal extravasation is usually averted.

Pulmonary inflammation and abscess from escape of liver pus into the lungs are sometimes discovered post mortem. Generally the pulmonary abscess communicates with the mother abscess in the liver by a small opening in the diaphragm, the pleural sac being shut off by adhesions.

Liver pus.— The naked-eye appearance of liver pus is peculiar. When newly evacuated it is usually chocolate - coloured and streaked with, or mixed with, larger or smaller clots or streaks of blood,