No. 1, May, 1921] PATHOLOGY 77 



possibility of introduction of serious diseases into China through the large importation of 

 American cotton seeds, and urges the Chinese cotton growers to practise the precaution of 

 seed fumigation. — Chunjen C. Chen. 



530. Cook, Mel. T. The Altemaria fruit rot and Rhizoctonia stem rot of tomatoes. 

 [Abstract.] Phytopath. 10: 59. 1920. 



531. Cook, Mel. T. Blossom blight of the peach. [Abstract.] Phytopath. 10: 64-65. 

 1920. 



532. Cook, O. F. A disorder of cotton plants in China: Clubleaf or cyrtosis. Jour. 

 Heredity 11 : 99-110. / pi-, fig. 1-9. 1920.— A disease of the mosaic type is described as being 

 destructive to cotton in China. Diseased plants develop a large number of shoots which 

 give them a "witches' broom" appearance. The nodes are short and the leaves small and 

 crinkled, often colored different shades of green, yellow, and red. The disease is believed to 

 be infectious. Leafhoppers are suspected as agents of dissemination. — C. W. Bennett. 



533. Cromwell, Richard O. Recent studies on Septoria of wheat. [Abstract.] Phyto- 

 path. 10:51. 1920. 



534. Delacroix, Jorge. Enfermedades de las plantas cultivadas. Enfermedades no 

 parasitarias. [Diseases of cultivated plants. Non-parasitic diseases.] 12 X 18 cm., 392 p., 

 57 pi. Casa Editorial, P. Salvat: Barcelona, 1920. — A Spanish translation from the French 

 edition, published as part of the "Enciclopedia Agricola." — John A. Stevenson. 



535. Delacroix, Jorge, t Andres Maublanc. Enfermedades de las plantas cultivadas. 

 Enfermedades parasitarias. [Diseases of cultivated plants. Parasitic diseases.] 12 X 18 

 cm., 457 p., 87 pi. Casa Editorial, P. Salvat: Barcelona, 1919. — A Spanish translation from 

 the second French edition, published as part of the "Enciclopedia Agricola." — John A. 

 Stevenson. 



536. DuRRELL, L. W. The purple sheath spot of com. [Abstract.] Phytopath. 10: 54-55. 

 1920. 



537. Gloyer, W. O. Apple blister canker. [Abstract.] Phytopath. 10:58. 1920. 



538. Hartley, Carl, and Glenn G. Hahn. Notes on some diseases of aspen. Phyto- 

 path. 10: 140-147. S fig. 1920. — Popultts tremuloides is found in certain regions to be unusu- 

 ally subject to disease. Trunk cankers in these regions seem to be important factors in short- 

 ening the life of the trees. Fomes igniaritis is a frequent cause of premature death. The 

 occurrence is also noted of (1) a twig blight suggesting in appearance the fire blight of pear; 

 (2) leaf killing by Sclerotium bifrons E. & E., found in both the East and the West, and also 

 attacking Lombardy poplar; (3) a bark blackening of obscure origin which prevents propa- 

 gation by cuttings. — Carl Hartley. 



539. Harvey, E.B. Some enemies of the potato. Sci. Amer. Monthly 2: 120-122. Fig. 1-9. 

 1920. — The mechanism by which the hyphae of the "damping-off" fungus, Pythium deBarya- 

 num, push through a cell wall barrier is described. Experimenting with slices of potato 3 

 or 4 cells thick and watching the process through the microscope, it was found that a hypha 

 penetrates the cell wall in 5 minutes. The author believes that this is entirely too short a 

 time to account for the breaking down of the cell wall by enzyme action. Zoospore dispersal 

 of Phytophthora infestans is also illustrated. — Chas. H. Otis. 



540. HoLBERT, J. R., AND G. N. HoFFER. Com root and stalk rots. [Abstract.] Phyto- 

 path. 10: 55. 1920. 



541. Jones, Fred RuEL. Pythium as a causal factor in "pea blight." [Abstract.] Phyto- 

 path. 10:67. 1920. 



