272 PATHOLOGY [Bot. Absts., Vol. V, 



botic). Cold wet springs are favorable to the disease. Trees are very susceptible up to the 

 eighth year. Indications are that fungus gains entrance at time of budding or grafting. — 

 Somewhat similar disease of apricots is said to be caused by Nectria cinnabarina. — Differen- 

 tial stain for mycelium of these two organisms in wood is: very weak solution Delafield's 

 haematoxylin, 24 hours, differentiated in ammoniated distilled water. [See also next preced- 

 ing Entries, 2073, 2074.]— D. Reddick. 



2076. Nicholson, C.G. Some vegetable parasites. Sci. Amer. 122 : 87-97. 4 fig. 1920.— 

 A popular article on flowering plants and fungi that derive nourishment from other plants.— 

 Chas. H. Otis. 



2077. Osborne, T. G. B. Black leg disease of cabbages. Jour. Dept. Agric. South 

 Australia 23 : 107-110. 1 fig. 1919. — The article contains a brief summary of the history of 

 the disease in South Australia. A detailed description of the symptoms, and remedial meas- 

 ures based upon K. P. Henderson's work (Phytopathology 7: 379-431. 1918) is given.— 

 Anthony Berg. 



2078. Osborne, T. G. B. Two serious new wilt diseases. Jour. Dept. Agric. South Aus- 

 tralia 23 : 437. 1919. — Two serious wilt diseases hitherto unrecorded in the state have come 

 to the attention of the author. The one a spotted wilt of tomato which develops on the young 

 leaves, leaf stalk and stems in irregular, brown spots and within a few days the whole plant 

 wilts from above downward. The other is a strawberry wilt. Apparently healthy plants wilt 

 within a few hours in hot weather; though seldom killed outright the first season the plants 

 fail to make thrifty growth or to bear fruit. The disease can be spread by planting offshoots 

 from diseased plants. Healthy plants set out in beds that had a diseased crop the previous 

 season become affected. — Anthony Berg. 



2079. Osmaston, A. E. Observations on some effects of fires and on lightning-struck 

 trees in the chir forests of the North Garhwall Division. Indian Forester 46: 125-131. 1920. 

 — Chir forests were badly burned in 1916 and the trees apparently have not been killed by heat 

 directly but through the subsequent action of insects, especially bark beetles, and fungi. 

 Similar action is seen in trees struck by lightning, the infection spreading to surrounding trees 

 in the group. This may be due to electrical disturbances and action on the cambium as well 

 as to external agencies. — E. N. Munns. 



2080. Osterwalder. Vom Apfelmehltau. [Apple mildew.] Schweiz. Zeitschr. Obst. u. 

 Weinbau 1918: 161. 1918. — Sulfur and lime-sulfur solution are worthless for control. Best 

 control is early careful cutting and burning of infected twigs. The following varieties are 

 very susceptible: Parkers Pepping, Orleans- and Landsberger-Reinette, Goldreinette von 

 Blenheim, Boiken. [Through abst. by Matouschek in Zeitschr. Pflanzenkr. 29: 261-262. 

 1919 (1920).]— D. Reddick. 



2081. Paine, S. G., and C. M. Haenseler. Decay in potato clamps due to "black-leg." 

 Jour. Ministry Agric. Great Britain 27: 78-80, 1920. — Cultural studies indicate that some of 

 the trouble from the rotting of potatoes in out-door storage in Britain during the winter of 

 1918-19 was due to the "black-leg" organism (Bacillus atroseplicus) . It is not certain whether 

 it was responsible for the initial injury or whether its presence was general in rotting potatoes 

 throughout the country. — M. B. McKay. 



2082. Pammel, L. H. Perennial mycelium of parasitic fungi. Proc. Iowa Acad. Sci. 25: 

 259-263. 1920. — The author enumerates many species of fungus with perennial mycelium. 

 Of Ustilago striaeformis he states "The purpose of this note is to call attention to the fact that 

 the same stool of timothy will produce the smut for years." — H. S. Conard. 



2083. Peyronel, B. Sul nerume o marciume nero delle castagne. [On the blackening or 

 black rot of chestnuts.] Staz. Sperim. Agrarie Italiane 52: 21-41. 4 pi- 1919. — A study of 

 the black rot of chestnuts, a condition distinctly recognizable in the ripe fruit but which, 



