In the sentence:
...quō ubi accēpit, in agrum quem arāverat magnā cum dīligentiā sparsit.
quo could either be the adverb meaning where/whereupon, or it could be the relative pronoun, assuming that accipio takes the ablative. however, the object of the previous sentence (dentes) is plural, so I am leaning towards regarding quo as the adverb here, but in that case it is confusing because both quo and ubi mean "where", so why would we have two words in a row both meaning the same thing?