REPORT OF THE SOCIETY 79 



that it adds to the trouble of making Bordeaux and that it is not so handy as 

 arsenate of h'me. On the other hand, it is very cheap and effective and, when 

 properly made, safe on foliage. A large number of farmers in New Brunswick 

 have been using this mixture for the past three years with good satisfaction. 

 We named the mixture of hydrated lime and dust collector arsenic "D. E. L. 

 Mixture", the initials of the Dominion Entomological Laboratory where we 

 worked the formula out. 



As I stated in the beginning, just where to begin and where to end in such 

 a paper as this is debatable. White arsenic is the basis for practically all of our 

 arsenicals, but practically all pui poses other than the ones I have outlined call 

 for one or more factory operations before white arsenic can be made useful. 



I can see no large use foi white arsenic direct with the exception of its use 

 in baits, especially in view of the wonderful improvements that are now being 

 made in the cost of manufacturing combined arsenicals and in the arsenicals 

 themselves. 



CULTURAL CHARACTERISTICS OF CERTAIN SPECIES OF FUSARIUM. 

 by T. G. Major, B. S. A., M. Sc. 



In undertaking these investigations the object has been to study the reac- 

 tions of a number of species of the genus Fusarium (Link), found in root lesions, 

 when grown under vaiious cultural conditions. The difficulty of identifying an 

 organism, even in pure culture, with descriptions in the literature, is well known 

 since the medium is but seldom mentioned, and frequently the same fungus 

 grown on two different media exhibits very different types of giowth. This 

 variation involves not only the type, amount and rate of growth, and colour 

 production, but also the presence or absence of spores, size of spores and other 

 microscopic characters. The investigations, the results of which aie here pre- 

 sented in an abridged form, had the main object of determining to what extent 

 an organism varies under known cultural conditions, with a view to its classifica- 

 tion. In preparing this paper it has been found necessary to leave out most of 

 the detailed lesults and tj present only the methods, in brief, and the general 

 results and conclusions reached. The original work itself was very limited in 

 its scope, owing to the time factor, and the conclusions drawn can, at the most, 

 only be regarded as suggestive. 



Contiibution No. 18, Dept. of Botany, Macdonald College, Que., being 

 an abridgment of a thesis submitted to the Graduate Schjol of McGill Univ- 

 ersity, in partial fulfillment of the requirements for the degree of M. Sc, 1922. 



