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Root-nodules of the Leguminosae . 
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DESCRIPTION OF PLATE XIII. 
Illustrating Dr. Ethel R. Spratt’s paper on Root-nodules of the Leguminosae. 
P. = root; v.s. = vascular strand; b.t. = bacteroidal tissue; i.t. — infection thread; m. = meristem ; 
S.t. = root-stele; c. = outer protective layers; n. == nucleus; 0. = nucleolus; N. = nodule. 
Fig. 1. Roots of Lupinus with nodules. Nat. size. 
Fig. 2. Roots of Phaseolus with nodules. Nat. size. 
Fig. 3. Roots of Lotus corniculatus with nodules. Nat. size. 
Fig. 4. Roots of Acacia with nodules. Nat. size. 
Fig. 5. Roots of Vicia Faba with nodules. Nat. size. 
Fig. 6. Part of longitudinal section of a root of Vicia Faba , showing the cortical cells (c.cl), 
some of which, i.c., have become infected with Bacillus radicicola. x 325. 
Fig. 7. Longitudinal section of nodule of Vicia Faba . x 325. 
Fig. 8. Transverse section of nodule of Lupinus, showing three zones of bacteroidal tissue. 
p. = phellogen ; s. = thick-walled cells, x 70. 
Fig. 9. Transverse section of nodule of Phaseolus. p. = phellogen ; y. = styloids. x 70. 
Fig. 10. Bacteroidal cells of Lathy rus odoratus, showing nuclear changes, v. = vacuole, x 325. 
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