294 
Journal of Agricultural Research 
VoL XXUI, No, 4 
They are, however, frequently invaded during the period of storage by 
various filamentous fungi, in part saprophytes. In the light of this con¬ 
ception of skinspot we can understand the failure of this disease to 
spread in the United States in spite of numerous and continuous impor¬ 
tations of infested material. We may further rest assured, so far as our 
knowledge of powdery scab goes, that the skinspot stage of the latter 
can never become a serious menace to the potato industry in this country. 
The term skinspot has no right to existence, except perhaps for practical 
convenience as a designation of a certain stage of powdery scab. 
LITERATURE CITED 
(i )~C ARRUTHERS , William. 
1904. diseases op plants, potatoes. In Jour. Roy. Agr. Soc. England, 
v. 6 z, p. 261-265, fig. 1-2. 
(2) Gfissow, H. T. 
1918. OBSERVATIONS ON OBSCURE POTATO TROUBLES. II. UNFAVORABLE 
storage conditions. In Phytopathology, v. 8, no. 9, p. 492-493, 
fig. 3. 
(3) Kunkel, L. O. 
1915. A contribution to the life history of spongospora subterranea. 
(A preliminary report.) In Jour. Agr. Research, v. 4, no. 3, p. 
265-278, pi. 39-43. Literature cited, p. 278. 
(4) Melhus, I. E., Rosenbaum, J., and Schultz, E. S. 
1916. SPONGOSPORA SUBTERRANEA AND PHOMA TUBEROSA ON THE IRISH POTATO. * 
In Jour. Agr. Research, v. 7, no. 5, p. 213-254, 1 fig., pi. A (col.), 
7-14. Literature cited, p. 253. 
(5) Milburn, Thomas, and Bessey, E. S. 
1915. FUNGOID DISEASES OF FARM AND GARDEN CROPS. X, Il8 p., 31 fig. 
London, New York, etc. 
(6) O’Brien, D. G. 
1919. RHIZOCTONIA DISEASE, OR STEM ROT, ON POTATOES. In Scot. Jour. Agr., 
v. 2, no. 4, p. 482-491, 4 fig., 12 pi. Bibliography, p. 490-491. 
(7) Owen, M. Nest. 
1919. THE SKIN SPOT DISEASE OF POTATO TUBERS. (OOSPORA PUSTULANS.) 
In Roy. Bot. Gard. Kew Bui. Misc. Inform., 1919, no. 8, p. 289-301, 
2 fig., pi. 11. 
(8) Pethybridge, George H. 
1915. investigations on potato diseases. (Sixth report.) Dept. Agr. and 
Tech Instr. Ireland Jour., v. 15, no. 3, p. 491-526, 16 fig. (on 12 pi.). 
(9) Pratt, O. A. 
1916. A WESTERN FIELDROT of THE IRISH POTATO TUBER CAUSED BY FUSARIUM 
radicicola. In Jour. Agr. Research, v. 6, no. 9, p. 297-310, pi. 
34 - 37 - 
(10) WoLLENWEBER, H. W. 
1920. DER KARTOFFELSCHORF. in. die pustelfaule. In Arb. Forschungf • 
inst. Kartoffelbau, Heft 2, p. 73-74, fig. 9. 
