Which preposition to use with modius

of Occurrences 2%

In fact we are bound on general evidence to assume for our own period that he is in the main right; the poor freeman of Rome had to live somehow, and the cheap corn which he enjoyed was not given him gratis until a few years before the Republic came to an end.[330] How did he get the money to pay even the sum of six asses and a third for a modius of corn, or to pay for shelter and clothing, which were assuredly not to be had for nothing?

for Occurrences 1%

For food they are given dry wheat, usually a half modius for every one hundred and twenty doves.

Which preposition to use with  modius