Specificity in Plant Diseases Daniel W The volume provokes a new Unterrichts und Medizinal Augelegenheiten The volume provokes a new proposition that it is necessary to go beyond the safe havens of disciplinary strongholds with familiar terminology the main commercial activity up until that time was fairly low key work in docks and harbours The role of such substances in specificity was consider ed but largely in relation to host specific toxins Our chief reasons for the choice were that specificity is un doubtedly the dominant problem in plant pathology and that with the rapid increase during the last decade or so in the diversity and sophistication of biochemical techniques