8 



CIRCULAR 6 3 5, U. S. DEPARTMENT OF AGRICULTURE 



various parts of the world as infesting opium, reel pepper, rice, 

 paprika, turmeric, saffron, spices, licorice, pyrethrum powder, bran, 

 belladonna, raisins, dried figs, and corn meal. 



Tobacco Moth 



The tobacco moth is widely distributed throughout the Temperate 

 and Tropical Zones of the world. It is at present the most serious pest 

 of flue-cured and imported cigarette tobaccos in storage in the United 

 States. Because of its preference for a limited number of tobacco 

 types, however, it is not of such universal concern to the tobacco trade 

 as is the cigarette beetle. 



STAGES OF THE MOTH 



The adult is a small, grayish moth, somewhat variable in color, some 

 adults being distinctly gray and others brownish gray. It measures 



Figure 5. — Stages of the tobacco moth : A, Eggs attached to tobacco leaf ; B, full-grown 

 larva ; C, pupa ; D, adult. A 10 times, B 6 times, C 9 times, and D 7 times natural size. 



about three-eighths of an inch from head to tips of the folded wings 

 and has a wing spread of about five-eighths of an inch. The average 

 longevity of adults is about 8 days in summer and about 14 days in 

 the cooler weather of spring and fall. Mating and egg laying may 

 begin within 24 hours after emergence. The maximum number of 

 eggs laid by 1 female is about 275. 



The eggs are grayish white when laid, turning brown or red during 

 incubation. They are about one-fortieth to one-fiftieth of an inch 

 long and, though visible to the naked eye, are not easily found on 

 tobacco. They are laid singly, sometimes grouped closely, on or as 

 near to the tobacco as possible. The incubation period is 4 to 5 days 

 in summer and ranges from 6 to 17 days in cooler weather. 



The larva of the tobacco moth is usually tinged with pink, although 

 there is considerable variation in color, some larvae being creamy 

 white or brownish. The head is reddish brown and the body has rows 

 of small brown spots along the back. When full-grown the larvae 

 measure about three-eighths to one-half inch in length. They ex- 



