The Formation of Vegetable Mould Through the Action of Worms: With Observations on Their Habits

accumulated acid action alimentary canal amount animals apex appear base become believe beneath bodies broken brought buildings buried burrows castings cent chalk close Cloth collected completely concrete considerable consisted contained course covered depth diameter disintegration distance doubt dragged drawn earth ejected extremely fact feet field fine floor flow formed fragments fresh given gizzards glands grass greater ground half heavy holes Illustrations inches in thickness inclined kinds land layer leaves length less light live lower manner matter means measured middle mouths nature nearly objects observed occasions particles petioles places plants ploughed plugging points present probably rain remains removed result rolled sand seen seized side slope soil sometimes species square stones subsided surface swallowed tiles tips trench triangles turf upper vegetable mould walls washed weather weight whole worms yards