Professor Huxley's article on ‘Bos, Bentley, and Byron’ was delightful to read; it provokes these thoughts of mine.

Majority opinion proves nothing, but it is solidly on the side of bos piger. Kiessling, for instance, and F. Villeneuve (in his 1967 Budé text) place the comma after piger. So do Lewis and Short, the TLL, the compilers of the new Oxford Latin Dictionary, and Dominicus Bo in his Lexicon Horatianum. Acron, Pseudo-Acron, and Porphyrion offer no comment. Piger is attached to caballus by Lane Cooper, and rather hesitantly by A. S. Wilkins. The latter felt that this better fitted the general sense of Horace's argument, a point to which I recur later. Wilkins was less confident of the rhythm of the line as a pointer to the ascription, and mentioned that many (unspecified) editors took piger as going with both nouns; this, indeed, might be an attractive compromise.