444 THE BIOLOGY OF INSECTS 



the source of their chief ingredient. The typical lac insect 

 {Tachardia laced), which has been fully described by 

 A. D. Imms and N. C. Chatterjec (191 5), inhabits large 

 tracts of India and Burma, and is found on a great variety of 

 trees which " contain a gummy or resinous fluid or are rich 

 in latex " ; thus material is provided for the epidermal 

 secretion which hardens to form the lac or protective 

 " scale " covering the body of the mature female. The 

 name 'Mac " (" lakh " in Hindi), which can be traced back 

 to Sanskrit, means a hundred thousand, *' in allusion to 

 the multitude of larvae of the insect that are present during 

 the period of larval emergence." The various forms of 

 Tachardia lacca are bright red in colour, and the name 

 reappears in the artist's crimson " lake," a pigment extracted 

 from the insects' bodies ; the insect-origin of this colour was 

 known in Europe seventeen hundred years ago. Tachardia 

 is preyed upon by a great variety of insects, the most 

 formidable being the caterpillars of the noctuid moth 

 Eublemma amahilis ; a heavy mortality follows naturally 

 because the prolific reproduction of the lac insect provides 

 abundant food for its enemies, so that these can multiply 

 at a rate which threatens at times to exterminate their 

 victims, a result which on account of the economic value 

 of Taccardia would be deplored by cultivators. In this 

 instance the predaceous insects are reckoned to be harmful, 

 whereas most creatures which devour Coccidae — a family 

 on the whole distinctly destructive — are hailed by mankind 

 as benefactors. 



Examples of the relations between insects and mankind 

 have now been given in sufficient number to illustrate how 

 various in their nature and in their effect on human life 

 such contacts are. When we think of the myriad insects 

 that devour crops, live as parasites in or on domestic animals, 

 invade man's own body, suck human blood and inoculate 

 his system with germs causative of dread diseases, it may 

 seem fitting that the name of the old Eastern divinity who 

 was worshipped as Baalzebub, the " Lord of Flies," should 

 have been transferred later to the author of evil. But we 



