en adhesions have
formed between the iris and the structures in relation to it, the pupil
dilates irregularly under atropin. Although complete recovery is to be
expected under early and energetic treatment, if neglected, _iritis_ may
result in occlusion of the pupil and permanent impairment or loss of
sight.

The other lesions of the eye are much rarer, and can only be discovered
on ophthalmoscopic examination.

The virus of syphilis exerts a special influence upon the _Blood
Vessels_, exciting a proliferation of the endothelial lining which
results in narrowing of their lumen, _endarteritis_, and a perivascular
infiltration in the form of accumulations of plasma cells around the
vessels and in the lymphatics that accompany them.

In the _Brain_, in the later periods of secondary and in tertiary
syphilis, changes occur as a result of the narrowing of the lumen of the
arteries, or of their complete obliteration by thrombosis. By
interfering with the nutrition of those parts of the brain supplied by
the affected arteries, these lesions give rise to clinical features of
which severe headache and paralysis are the most prominent.

Affections of the _Spinal Cord_ are extremely rare, but paraplegia from
myelitis has been observed.

Lastly, attention must be directed to the remarkable variations observed
in different patients. Sometimes the virulent character of the disease
can only be accounted for by an idiosyncrasy of the patient.
Constitutional symptoms, particularly pyrexia and anaemia, are most often
met with in young women. Patients over forty years of age have greater
difficulty in overcoming the infection than younger adults. Malarial and
other infections, and the conditions attending life in tropical
countries, from the debility which they cause, tend to aggravate and
prolong the disease, which then assumes the characters of what has been
called _malignant syphilis_. All chronic ailments have a similar
influence, and alcoholic intemperance is universally regarded as a
serious aggravating factor.

_Diagnosis of Secondary Syphilis._--A routine examination should be made
of the parts of the body which are most often affected in this
disease--the scalp, mouth, throat, posterior cervical glands, and the
trunk, the patient being stripped and examined by daylight. Among the
_diagnostic features of the skin affections_ the following may be
mentioned: They are frequently, and sometimes to a marked degree,
symmetrical;