Sentence:  As touching the galls, which by ouermuch riding on horseback be incident to the twist and the inner parts of the thigh, as euery man knoweth full well, which do burne and chaufe the skin in those parts; the fomie slime which a horse yeeldeth, as well from his mouth as his <WSD>cullions</WSD>, is soueraigne therefore, if the place be annointed therwith. 
Meaning of the word marked with <WSD> tags:  Testicle.