i37^> 



MICANS OF PRKVHNTIOX AND CONTUOI, 



parallela n. sp., on Acey nigrum i\lichx., at Byron (Ontario). ()ctober-Xo- 

 veniber 1903 ; stroniata containing 5 to 15 ])ycnidia, scattered irregularly 

 or arranged in more or less continuous parallel lines; 3) Ascochyta Achlydis 

 n. sp., on Achlys triphylla U. C, in the island of Vancouver, 9th June 1915 ; 

 on the leaves attacked spots are observed, some of which are small in size 

 (2 mm.) ; others, fewer in number, are i cm. in diameter and have a dark 

 red border; 4) Diplodia Niittcilliae n. sp. on NitttalUa cerasiformis Tovr. and 

 Or., at Victoria (British Columbia) , April 1915 ; the pycnidia are placed round 

 the lenticels, which likewise serve as a passage for the parasite ; 5) Septoria 

 adenocaulonis n. sp., on leorvesoi Adenocaidon bicolor Hook, in British Colum- 

 bia, May 1915; 6) S. angtdaris Dearness and Bartholomew n. sp., on leaves 

 of SoUdago latijolia L. at Komoka (Ontario), June 1913 ; 7) S. lupincola n. 

 sp., on leaves of Lupinus perennis h-, at Oakland, near London (Ontario), 

 July 1915 ; 8) S. sanguinea n. sp., on Ribes sangninenm Pursh, in British 

 Columbia, September 191 2 ; 9) S. Macrosporia n. sp., on Chrysanthemum 

 Leucanthemum, at London, October 1915 ; 10) Leptostromella conigena n. 

 sp., on cones of Picea Abies (L-) Karst., at London, April 1915 ; 11) Melan- 

 coniitm pannilum Dearness and Bartholomew n. sp., on dead branches of 

 Betida popidijolia Marsh, along the south-eastern shores of Lake Huron 

 (Ontario), May 1912. 



Further mention is made of Cylindrosporiiim. Crataegi Ellis and Ev., 

 on leaves of Crataegus brevispina in British Columbia, September 1914 ; 

 C. Toxicodendri (Curtis) Ellis and Ev. on living leaves of Rhus Toxicoden- 

 dron, etc. ; Ramnlaria Lapsanae (Desni.) Sacc, on Lapsana cnmmums L- 

 at Elgra (Ontario), July 1915, etc. 



MEANS 

 OF PREVENTION 

 .4ND CONTROL 



1031 - Seed Sifting as a Means of Controlling Fungous Diseases. — hknning Ernest., 



in Kungl. Landtbruks-Akadcmiens Handliu'^ar och Tidskritt, I,th. Year, No. 4, pp. 282-300. 

 Stockholm, 191 6. 



According to ZimmeRMANN, the mycelia of certain parasitic fungi 

 may retain their vitality for five years in the seeds of grass plants. The 

 writer had satisfied himself a long time ago that the appearance of Ustilago 

 Tritici was clearly related to the time and conditions of flowering. While 

 it occurs very rarely on i?o;'(ie"7/-AW disiichum erectum, with clo.se ear, which dur- 

 ing the phase of fertilisation keeps its flowers entirely enclosed in the glumes, 

 it is on the other hand very frequent in H. disiichum nutans, with loose ear 

 and in which at the time of fertilisation the flowers at the tip and sometimes 

 those at the base of the inflorescence open. At that moment, the numerous 

 spores of Ustilago carried by the wind penetrate the floral organs, grow and 

 take up their abode in the mass of the grain. For loose-eared \-arieties of 

 barley therefore it would be desirable to remove these infected grains at the 

 time of sowing. A feature by which they may be distinguished is their size. 

 The grains inserted at the tip and at the base of the inflorescence are distin- 

 guished by smaller bulk, and between the bulk of the grains and the per- 

 centage of infected plants, as the Author was able to prove by many experi- 

 ments, the following inverse ratio exists : 



