skin, the desquamation of which shows that the poison
went to the surface without producing the usual state of inflammation,
or the rash peculiar to the disease. This form, called _scarlatina sine
exanthemate_, is extremely rare.

16. THE MALIGNANT FORMS OF SCARLET-FEVER

are caused by the character of the epidemy, but, perhaps, more
frequently by the weak and sickly constitution of the patient and the
external circumstances affecting it. Thus, persons of scrofulous habit,
being naturally of a low organization, without much power of resistance,
are much more liable to experience the destructive effects of scarlatina
than those whose organism possesses sufficient energy to resist the
action of the morbid poison, and to expel it before it can do any
serious harm inside the body.

17. SUDDEN INVASION OF THE NERVOUS CENTRES.

Of the different forms of scarlatina maligna the most dangerous is the
sudden invasion of the nervous system, particularly the _brain_, the
_cerebellum_ and the _spine_, by which the patient's life is sometimes
extinguished in a few hours. In other cases the symptoms deepen more
gradually, and death ensues on the third, fifth or seventh day.

18. AFFECTION OF THE BRAIN.

When the _brain_ is affected, the patient suddenly complains of violent
headache, vomits repeatedly, loses his eye-sight, has furious delirium,
or coma (a state of sleep from which it is difficult to rouse the
patient); his pupils dilate; the pulse becomes small, intermits;
sometimes the skin becomes cold; there is dyspnoea (difficulty of
breathing), fainting, paralysis, convulsions, and finally death; or,
sometimes, the paroxysm passes suddenly by with bleeding from the nose
or with a profuse perspiration.

19. AFFECTION OF THE CEREBELLUM AND SPINE.

In affections of the _cerebellum_ and _spinal marrow_, the patient
complains of violent pain in the back of the head and neck, in the
spine, and frequently in the whole body. These also frequently terminate
with the destruction of life.

20. During all these invasions of the nervous centres there is little or
no rash, and what appears is of a pale, livid hue.

21. PUTRID SYMPTOMS.

Next to those most dangerous forms--most dangerous, because the organic
power (the _vis medicatrix naturae_), from which the restoration of
health must be expected, and without which no physician can remove the
slightest symptom of disease, becomes partly paralyzed from the
beginning-