HOUSEHOLD INSECTS 99 



Animal foods, such as hams, dried meats, and cheese are 

 frequently damaged by the larva^ of certain beetles and flies 

 which normally occur in carrion, skins, and similar substances. 

 One of these, the cheese-skipper, is the larva of a small fly, 

 Piophila casei, quite thoroughly domesticated as an inhabi- 

 tant of cheese. Its name is derived from the power of the 

 larva to skip or jump by bending and then suddenly straight- 

 ening the body. If these larviv are accidentally swallowed 

 they are able to withstand the action of the digestive fluids 

 and may cause very distressing symptoms. The larva' of 

 quite a number of other insects, mainly flies of various kinds 

 are also capable of remaining alive in the alimentary tract, 

 and others develop regularly beneath the skin of animals or 

 in their alimentary tracts. Species known to affect man be- 

 neath the skin are very rare and restricted to the tropics but 

 two conuuon species affect cattle in this way in Europe and 

 North America and are the cause of considerable loss. Af- 

 fections of this sort are known by the general name of myiasis 

 and human cases are fortunately of uncommon occurrence. 



One of the most versatile of the pantry insects is the so- 

 called "drug-store beetle" (Sitodrepa panicea), formerly of 

 common occurrence in apothecary shops where it fed u])on 

 the stores of spices, aromatic roots, red pepper and ill-smell- 

 ing or strongly flavored plant materials. The fondness shown 

 by the grubs of this beetle for ginger and cayenne pepper is 

 quite remarkable for such substances would seem to be rather 

 pungent for a regular diet. Even dry tobacco forms the fa- 

 vorite food of the related cigarette beetle {Lasioderma serri- 

 corne), the larvae of which sometimes riddle cigars with their 

 food burrows. 



This is only a very small part of the varied series of insect 

 guests which we house and noiu-ish, and which add to the 

 complexity of modern life. However annoying they may be, 

 we must admire them for the persistence with which they 

 force themselves upon us. 



