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INJURIOUS INSECTS AND FUNGI. 



[June 1895. 



enhanced. In steam flour mills there is naturally a high 

 temperature in certain parts, and throughout them a higher 

 temperature is maintained than in ordinary mills, which is 

 favourable to the development and rapid spread of the moth. 



In 1889, there was a great scare concerning this insect in 

 Canada. It was found to have infested a mill in one of the 

 large Canadian milling centres to such an extent that the mill 

 was closed, and orders were issued by the Government that 

 before the work was continued every part of it and its machinery 

 should be thoroughly disinfested. By this precaution, and the 

 thorough execution of the orders given by the authorities, the 

 mill was soon freed from the insect. But the millers paid little 

 attention to this subject, and in 1890 it had become so common 

 that it was necessary for the Provincial Board of Health of 

 Toronto to send out a circular to apprise the millers that in- 

 spectors would be sent to examine their mills and condemn any 

 infested produce therein. Many of these millers were ignorant 

 of the presence of the moth, and of its nature and habits ; and 

 without doubt many millers and flour dealers in this country are 

 equally unaware of this infestation. It is unfortunately pre- 

 valent in many mills and flour and corn stores, causing great 

 loss and inconvenience. 



History and Habits. 



The moth Ephestia Kuhniella belongs to the genus Ephestia 

 of the family Phycidse. * It is about an inch across the wings 

 and half an inch long (Fig. 2). It is shown at rest, with its 

 wings folded, in Fig. 1 . The upper wings are pale grey with 

 dots or splashes of darker colour, and transverse markings, while 

 the hind wings are glossy white with dark margins. The egg- 

 is oval, white, and just discernible without a glass. The female 

 lays a large quantity of eggs. Professor Riley states that an 

 anatomical examination showed the number of eggs in a single 

 female to be 678. The eggs are laid upon sacks and bags con- 

 taining flour or grain, upon the machinery, and in various parts 

 of the mill or stores. In four or five days, the larvae come from 

 the egos. At first, they can hardly be seen, but they grow very 

 quickly, attaining a size generally rather over five- eighths of an 

 inch (Fig. 5). In the early stages they are light red with brown 

 heads of disproportionately large size. Afterwards, they become 

 almost white. Upon the segments, near the head and tail, there are 

 brown patches. They have six feet and ten sucker feet. There 

 are a few bristles on every segment. The larvae remain in 

 this stage from three to four weeks and even longer in favour- 

 able circumstances, feeding upon the flour or upon the contents of 

 biscuits or even upon the grain itself. They produce fine silken 

 webs whose threads are sticky, and to which the flour, or grain 

 or biscuit morsels adhere. After a time, a spongy mass is formed 

 with numerous passages or galleries in which the larvae live and 



