e extensive and permanent pigmentation. This is
seen in its highest degree in itching diseases like prurigo and
pityriasis. Greenhow has published instances of this kind under the
name of "vagabond's disease," a disease simulating morbus addisonii,
and particularly found in tramps and vagrants. In aged people this
condition is the pityriasis nigra of Willan. According to Crocker in
two cases reported by Thibierge, the oral mucous membrane was also
stained. Carrington and Crocker both record cases of permanent
pigmentation following exposure to great cold. Gautier is accredited
with recording in 1890 the case of a boy of six in whom pigmented
patches from sepia to almost black began to form at the age of two, and
were distributed all over the body. Precocious maturity of the genital
organs preceded and accompanied the pigmentation, but the hair was illy
developed.

Chloasma uterinum presents some interesting anomalies. Swayne records a
singular variety in a woman in whom, during the last three months of
three successive pregnancies, the face, arms, hands, and legs were
spotted like a leopard, and remained so until after her confinement.
Crocker speaks of a lady of thirty whose skin during each pregnancy
became at first bronze, as if it had been exposed to a tropical sun,
and then in spots almost black. Kaposi knew a woman with a pigmented
mole two inches square on the side of the neck, which became quite
black at each pregnancy, and which was the first recognizable sign of
her condition. It is quite possible that the black disease of the Garo
Hills in Assam is due to extreme and acute development of a pernicious
form of malaria. In chronic malaria the skin may be yellowish, from a
chestnut-brown to a black color, after long exposure to the influence
of the fever. Various fungi, such as tinea versicolor and the Mexican
"Caraati," may produce discoloration on the skin.

Acanthosis Nigricans may be defined as a general pigmentation with
papillary mole-like growths. In the "International Atlas of Rare Skin
Diseases" there are two cases pictured, one by Politzer in a woman of
sixty-two, and the other by Janovsky in a man of forty-two. The regions
affected were mostly of a dirty-brown color, but in patches of a
bluish-gray. The disease began suddenly in the woman, but gradually in
the man. Crocker has reported a case somewhat similar to these two,
under the head of general bronzing without constitutional symptoms, in
a Swe