a before they are arrested in the lymphatics, and thus
several patches of inflammation may appear with healthy areas between.

The pus infiltrates the meshes of the cellular tissue, there is
sloughing of considerable portions of tissue of low vitality, such as
fat, fascia, or tendon, and if the process continues for some time
several collections of pus may form.

_Clinical Features._--The reaction in cases of diffuse cellulitis is
severe, and is usually ushered in by a distinct chill or even a rigor,
while the temperature rises to 103, 104, or 105 F. The pulse is
proportionately increased in frequency, and is small, feeble, and often
irregular. The face is flushed, the tongue dry and brown, and the
patient may become delirious, especially during the night. Leucocytosis
is present in cases of moderate severity; but in severe cases the
virulence of the toxins prevents reaction taking place, and leucocytosis
is absent.

The local manifestations vary with the relation of the seat of the
inflammation to the surface. When the superficial cellular tissue is
involved, the skin assumes a dark bluish-red colour, is swollen,
oedematous, and the seat of burning pain. To the touch it is firm, hot,
and tender. When the primary focus is in the deeper tissues, the
constitutional disturbance is aggravated, while the local signs are
delayed, and only become prominent when pus forms and approaches the
surface. It is not uncommon for blebs containing dark serous fluid to
form on the skin. The infection frequently spreads along the line of the
main lymph vessels of the part (_septic lymphangitis_) and may reach the
lymph glands (_septic lymphadenitis_).

With the formation of pus the skin becomes soft and boggy at several
points, and eventually breaks, giving exit to a quantity of thick
grumous discharge. Sometimes several small collections under the skin
fuse, and an abscess is formed in which fluctuation can be detected.
Occasionally gases are evolved in the tissues, giving rise to emphysema.
It is common for portions of fascia, ligaments, or tendons to slough,
and this may often be recognised clinically by a peculiar crunching or
grating sensation transmitted to the fingers on making firm pressure on
the part.

If it is not let out by incision, the pus, travelling along the lines of
least resistance, tends to point at several places on the surface, or to
open into joints or other cavities.

_Prognosis._--The occurrence of _septica