100 HOUSEHOLD INSECTS 



strip nailed along its upper edge on the inside to close 

 the opening between the frame of the screen and the 

 lower edge of the upper sash. It is fastened by two 

 buttons near the top and a hook on the inside at the 

 bottom which catches in a screw eye in the window sill. 

 This arrangement enables one to put the screen on and 

 fasten it from the inside of the house, which is of con- 

 siderable advantage, especially in the case of windows in 

 the upper stories. With this type of screen the upper sash 

 of the window should not be lowered, but the lower sash 

 can be raised or lowered at pleasure. 



In case of those houses that have shutters the screen 

 is sometimes made to fit the casing on the inside of the 

 window. In this case, the screen fits in front of the lower 

 sash only. The stops on the inside are usually removed 

 and the screen put in place of them. These screens are 

 arranged to slide up and down in order to gain access to 

 the lower sash and to close or open the shutters. With 

 one of these screens the lower sash should always be raised 

 to its full height when opened, else there will be a space 

 between it and the wire, and also between the two sashes 

 through which insects could easily crawl. 



So-called adjustable screens fitted beneath the lower 

 sash are practically worthless. They never fit tightly 

 enough to exclude mosquitoes, and with most of them 

 house-flies can easily enter. 



Every window and outside door in the house should be 

 screened. In the Southern states the screens should 

 remain on the year round. The same precaution is also 

 necessary to exclude house-flies. Front doors are often 

 screened while the back door is left unprotected, thus 

 forming a fine place of entrance for mosquitoes. Cellar 



