The above mentioned affixes [[5.1.18]] etc. come after a word in the 6th-Case in construction, in the sense of 'sown with so much'.,
The word वापः means 'sown therein' i. e. a field. Thus प्रस्थस्य वापः क्षेत्रं = प्रास्थिकम् 'sown with a Prastha', द्रौणिकम्, खारीकम्, i. e a field sown with a quantity of grain measuring a Prastha or a Drona or a Khari.,