32 



INJURTOCrS INSECTS AND FUNGI. 



[June 1895. 



published in the Annual Report of the Ontario Department 

 of Agriculture for 1889, it is stated that, in consequence of 

 an Order in Council, a steam stand-pipe with hose and other 

 connexions was erected on each flat of an infested mill. By 

 closing all doors and windows of each flat and turning on the 

 steam simultaneously in each floor the whole building was filled 

 with hot steam sufficient to kill anything. 



Spraying the machinery, walls, partitions, floors, beams, and 

 other parts with paraflan or carbolic acid solutions would no doubt 

 remove these insects, but it would not be possible to use these 

 extensively, as the flour would take up the smell and be spoiled. 



It is important that the dressing machinery and the flour 

 elevators should be of modern construction, so that the flour 

 may not be retained in corners and ridges. M. Danysz, in his 

 treatise, insists that round reels should always be used, and 

 not those with six sides. He also points out the importance 

 of fixing a brush on the straps on the elevators to which the 

 cups are fastened, in order to keep the sides clear of flour that 

 would harbour the larvae. 



M. Danysz strongly recommends the use of pyrethrum powder, 

 which is the base of several patent remedies used to destroy 

 black beetles, fleas, and other insects. It seems, however, that 

 the insect can only be reached by this powder in the moth stage. 

 It could not aflfect the chrysalis or the larvae. As there are 

 constant generations of this insect, at all events in mills where 

 the temperature is high, the process of dusting with pyrethrum 

 must be frequently repeajbed, and great care must be taken that 

 the powder does not get into the flour. 



This flour moth is most difficult to deal with, for obvious 

 reasons occurring to those who are acquainted with its life, 

 history, and habits. Great precautions are required to prevent 

 its entrance into mills and grain and flour storehouses, and when 

 it has gained a lodgment vigorous eflforts must be used to 

 dislodge it. 



A miller in a large way of business, whose mills are fitted 

 with machinery of the best and most modern construction, who 

 has suflTered much from this moth, believes that " cold air " is 

 the best way of exterminating it. This would entail stopping 

 work for a time and exposing all parts of the mill to the air in 

 cold weather. Exposure for two or three days to frost in winter 

 would effectually get rid of the insect. 



There is a species of Ichneumon Fly according to Mr. Klein 

 which destroys this moth, but, so far as can be ascertained, it 

 has not yet been identified. 



