Brown mites, Bryobia rubrioculus (Sch.), on almonds feed chiefly on upper leaf surfaces. Stylet punctures through the uppermost cuticle of epidermal cells are clescribed. It is estimated that the protoplasts of about zoo palisade cells were destroyecl in 30 minutes. When almoncl trees infested with brown mites were disinfested, they appeared to recover thereafter some of the lost green color. Apparent recovery after mite control related to normal increase in chlorophyll concentration during the period from bloom to June 1. Concentration of chlorophyll a and b (mgfgm of leaf tissue) increased in unclamagecl palisade cells while other, nearby palisade cells were being destroyecl. The rate of gain in chlorophyll concentration appeared to be similar for both clamagecl and undamaged almond leaves. Replacement of damagecl cells was not demonstratecl. Reduction in leaf area due to brown mite feeding from the beginning of the growing period until June r averagecl 29.8 %-