he seat of small abrasions,
haemorrhagic erosions, which may cause vomiting of blood and the
appearance of blood in the stools. Obstruction to the flow of blood from
the liver leads to dilatation of its blood-vessels, consequent pressure
upon the hepatic cells adjoining them, and their gradual loss of
function, or even atrophy and degeneration. In addition to the results
of such passive congestion exhibited by the stomach and bowel as noted
above, passive congestion of the liver is often accompanied by varicose
enlargement of the abdominal veins, in particular of those which
surround the lower end of the oesophagus, the lowest part of the rectum
and anus. In the latter position these dilated veins constitute what are
known as haemorrhoids or piles, internal or external as their site lies
within or outside the anal aperture.

Inflammatory lesions.

The mucous and serous membranes of the canal and the glandular elements
of the associated organs are the parts most subject to inflammatory
affections. Among the several sections of the digestive tract itself,
the oesophagus and jejunum are singularly exempt from inflammatory
processes; the fauces, stomach, caecum and appendix, ileum, mouth and
duodenum (including the opening of the common bile-duct), are more
commonly involved. _Stomatitis_, or inflammation of the mouth, has many
predisposing factors, but it has now been definitely determined that its
exciting cause is always some form of micro-organism. Any condition
favouring oral sepsis, as carious teeth, pyorrhoea alveolaris (a
discharge of pus due to inflamed granulations round carious teeth),
granulations beneath thick crusts of tartar, or an irritating tooth
plate, favours the growth of pyogenic organisms and hence of stomatitis.
Many varieties of this disease have been described, but all are forms of
"pyogenic" or "septic stomatitis." This in its mildest form is catarrhal
or erythematous, and is attended only by slight swelling tenderness and
salivation. In its next stage of acuteness it is known as "membranous,"
as a false membrane is produced somewhat resembling that due to
diphtheria, though caused by a staphylococcus only. A still more acute
form is "ulcerative," which may go on to the formation of an abscess
beneath the tongue. Scarlet fever usually gives rise to a slight
inflammation of the mouth followed by desquamation, but more rarely it
is accompanied by a most severe oedematous stomatitis with glossiti