126 
ALBAN STEWART 
SUMMARY OF LITERATURE CITED 
1. Crozier, A. A. Notes on Black Knot. Bot. Gaz. lo: 368-69. 1885. 
2. Duggar, B. M. Fungous Diseases of Plants. Ginn and Company, pp. 248-53. 
3. Farlow, W. G. The Black Knot. Bull. Bussey Inst. 1876, pp. 440-53. Pis. 4-6. 
4. Humphrey, J. M. The Black Knot of the Plum. Eighth Ann. Report Mass. 
Agr. Exp, Sta. 1890, pp. 200-10, pi. i. 
5. Lodeman, E. G. Black Knot. Bull. Cornell Univ. Agr. Exp. Sta. 81: 637-57. 
1894. 
6. Peck, G. H. Trans. Albany Inst. 7: 186-204. 1872. 
7. Solereder, H. Systematic Anatomy of the Dicotyledons. English translation. 
Vol. i, 1908, p. 309. 
DESCRIPTION OF FIGURES IN PLATES IX AND X 
All figures are of the choke cherry. Primus virginiana L. 
Plate IX 
Fig. I. Cross section of a portion of a normal stem. X 44. 
Fig. 2. Cross section of a portion of an infected stem at junction of uninfected 
and infected xylem. X 100. 
Fig. 3. Tangential section of normal wood. X 44. 
Fig. 4. Tangential section of a portion of a knot taken May 15, showing 
broadening of the rays. X 44. 
Fig. 5. Tangential section of a portion of a knot taken June 11, showing still 
further broadening of the rays. X 44. 
Fig. 6. Tangential section of infected xylem taken February 22, showing an 
early stage in the broadening of the rays. X 44. 
Plate X 
Fig. 7. Cross section of a portion of a mature knot, showing the outer ends of 
two xylem wedges, a broad ray between, and overturned xylem elements in the bark 
opposite the ray. X 44. 
Fig. 8. Cross section of a portion of an infected stem taken April 6, showing 
broad rays and parenchyma in the xylem, X 44. 
Fig. 9. Cross section of a mature knot. X about 5. 
Fig. 10. A more highly magnified portion of Fig. 7, showing uniseriate rays 
in overturned xylem segment. X 100. 
Fig. II. Radial section through a mature knot showing the general direction 
of some of the misplaced xylem elements, X 44. 
Fig. 12. Cross section of the outer portion of a knot, in an early stage, showing 
the removal of the outer part of the bark. X 44. 
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