DBook II CUTANEOUS INFECTIONS 183

psora and leprosy and the mild form of elephantia, but when it
is both inflamed and putrescent it causes virulent elephantia
of the kind that makes the patients horrible to look at; and it
likewise generates also the carbuncle that they call anthrax.

In my opinion, what we call impetigo is none other than what
the Greeks call psora and leprosy, and as recorded by Celsus
it has four varieties, according as it is more orless serious. From
this it is elear that impetigo is not lichen, as many translate it,
but that lichen is rather what I have called volaticae in the above
pages; for it arises from salty pituita, whereas impetigo arises
rather from black bile humor.

This is what, in the course of this discussion, I have to say
about infections of the skin. 'Those that are contagious are:
the plague bubo; those exanthemata which we call fersae and
variolae; certain ulcerated strumae??; some forms of lichen;
scabies, elephantia, achores, alopecia, syphilis, mentagra, and
any others there may be in which foul putrefaction developes.