430 Eumycetes. — Pflanzenkrankheiten. 



Clasterosporiwnt densum auf Faurea speciosa, Cercospora R?ioicissi 

 auf Rhoicissus, C. Withaniae auf W. sotnnifera. Neger. 



Trotter. Mycetum Tripolitanorum pugillus. (Ann. myc. X, 

 p. 509—514. 1912.) 



Der Verf. berichtet hier über eine mycologische Studienreise 

 nach der neuen italienischen Kolonie. Gesammelt wurde hauptsäch- 

 lich in der Umgebung von Tripolis, im ganzen 36 Arten, dar- 

 unter neu; Uromyces lihycns, Puccinia mediterranea , Aposphaeria 

 Rhois, Ascochyta tripolitana, Hyalothyridiuni leptitanum, Macropho- 

 tna Pithiiranthij Phoma nielicola, Septoria Polypogonis, Didymospo- 

 rium australe, Coniotheciuni Rhois. Die meisten übrigen sind we- 

 nigstens für das Gebiet neu. Neger. 



Wolf, F., A new Gnoynonia on Hickory leaves. (Ann. myc. X. 

 p. 488-491. 1 Taf. 1892.) 



Das früher wiederholt beschriebene Gloeosporium Cajyae wird 

 vom Verf. als die Conidienfructification einer Gnomonia erkannt, 

 welche er nun G. Caryae n. sp. nennt. Die Perithecien treten im 

 Frühjahr auf den abgefallenen Blättern von Carya ovata, der Coni- 

 dienzustand im Herbst an den noch lebenden Blättern auf. 



Neger. 



Ewapt, A. T., On Bitter Pit and the sensitivity of Apples 

 to Poisons. (Proc. Roy. Soc. Victoria. XXIV. 2. p. 367—419. 1912.) 



The author investigates the theory put forward by White that 

 the defect known as Bitter Pit in Apples may be associated with 

 the use of poisonous spraying materials. The result of his work 

 leads him to support that theory, though he recognises that Bitter 

 Pit sometimes occurs in cases where spraying has not been car- 

 ried out. 



The paper is derived into two parts, the first of which is con- 

 cerned with the sensitivity of Apples to poisons, and the second 

 with the Problem of Bitter Pit. It is found that the ripe pulp-cells 

 of apples are extraordinarily sensitive to various poisons. and it is 

 believed that minute quantities of dilute Solutions may penetrate 

 through the breathing pores in sufificient amount to produce Bitter 

 Pit. Young apples are more easily penetrated by dissolved poisons 

 than old ones, but their pulp-cells are more resistant. Hence a young 

 apple may absorb sufficient poison to kill a portion of its tissue 

 when adult, without any immediate toxic effect being shown. In 

 certain cases the poison may be absorbed from the soil. 



In conclusion it is stated that 3 points appear to be established 

 as facts, namely l) that Bitter Pit is, strictly speaking, not a disease 

 att all, but a symptone of local poisoning produced in the sensitive 

 pulp-cells of the apples, 2) that more than one poison may produce 

 it, and 3) that such poisons may be derived from more than one 

 source. A. D. Cotton. 



Laubert, R., Einige pflanzenpathologische Beobachtun- 

 gen. (Zeitschr. Pflanzenkrankh. XXII. p. 449—457. 1 Taf. 1912.) 



An den Wurzelausschlägen von Prunus acida (Dum.) K. Koch 



