66 



THE CANADIAN ENTOMOLOGIST. 



readily be seen how a few flies wintering over may give rise to millions of 

 flies in late summer. 



The prompt treatment of horse-manure with lime in special pits 

 should be insisted upon in towns and cities, but where flies are abundant 

 we must continue to use screens and sticky fly-paper to mitigate the 

 annoyance. 



Mosquitoes. — Here again, there are several species. The most 

 common form is perhaps Ctilex pwigeiis. The eggs are laid on the 

 surface of the standing water of ponds, marshes and rain-barrels ; the 

 wrigglers escape from the eggs in about 24 hours, and transform to pupae 

 in 10 or 12 days, and the adult mosquitoes make their appearance two or 

 three days after, a generation occupying, therefore, 14 to 16 days during 

 warm weather. As in the case of the house fly, the winter is passed in the 

 adult stage. It is now known that one species of mosquito is the cause of 

 m.ilaria and another of yellow-fever. 



Careful attention to water-barrels and the drainage of ponds and 

 marshes is absolutely necessary if freedom from mosquito attacks is 

 desired. A little kerosene poured on stagnant water containing wrigglers 

 will kill them. 



Fleas. — The most common flea is the Cat- or Dog-flea ( Piilex 



serraticeps) (Fig. 4). These are 

 sometimes very abundant in rooms 

 occupied by dogs and cats. The 

 eggs are deposited loosely among 

 the hairs of these animals, and often 

 drop to the floor or matting, where 

 the larvae develop, especially if the 

 mats are undisturbed and the floors 

 are not swept. Liberal dusting of 

 the infested animals and floors with 

 pyrethrum insect powder, the re- 

 newal of the mats for the dogs, and 

 the burning of the infested mats, will control fleas. 



Bed-bugs. — These disgusting insects (Cimex ledularia) sometimes 

 get into the houses of the most careful housekeepers, when travellers are 

 entertained. The cheaper hotels in many parts of the west are often 

 badly infested, and the bedrooms have a decided "buggy" odour. These 

 festive insects hide in the daytime in the cracks of the furniture and walls, 



(Tt.- 



Fig. 4. — Flea and its egrg, greatly magnified. 



