Sentence:  The large open leaves and large <WSD>knobby</WSD> leaves were picked out by hand, and formed the finest sort of "hyson skin" (known commercially as pretty good bloom, brightish hyson kind mixed, <WSD>knobby</WSD> leaf); the remaining leaves were hyson. 
Meaning of the word marked with <WSD> tags:  Having many knobs or knob-like projections.