Which preposition to use with pustules

in Occurrences 1%

As the pustules in chicken-pox very rarely run to the state of suppuration, as in the other disease, there is no fear of pitting or disfigurement, except in very severe forms, which, however, happen so seldom as not to merit apprehension.

of Occurrences 1%

Even the colored chef de cuisine, a muscular mulatto, with a beard of a rash disposition, coming out on wrong parts of his face in little eruptive pustules of black wool, sported his lines out of the galley-airholes, and his porgies were simmering in the pan while their memories were yet green in the submarine parishes from which they came.

Which preposition to use with  pustules