38 Annals Entomological Society of America [Vol. Ill, 



annoyance from this dermatitis, and wc know that the mite is 

 present generally, also those who attempt to use mattresses into 

 the construction of which the straws from these fields have entered 

 and indeed in even handling the same, the results of his agricul- 

 tural methods will be sent wherever, in the entire country, these 

 mattresses, or the straw itself, go into practical use within at least 

 a year from the time the wheat straw was harvested in the fields, 

 and thus people hundreds of miles away, with no possible means 

 of knowing of the presence of these mites in mattresses, are caused 

 not only great aggravation but intense suffering through their use. 



Preventive and Protective ^Measures. 



From the foregoing, it will be observed that that public pro- 

 tection from this skin disorder is onlv to be secured throusrh 

 revised agricultural methods of the. farmer, who, while offering 

 this protection, will also materially increase the profits of- his 

 business. Throughout the territory involved in the eastern 

 epidemic of this dermatitis, which, as has been shown, 'was due 

 to the excessive abundance of the Angoumois grain moth, the 

 evidence recently attained by the writer has been overwhelmingly 

 to the effect that where wheat was threshed as promptly as pos- 

 sible after harvest and directly from the shocks in the field, almost 

 no occurrence of this grain moth was observed by millers and 

 others handling the threshed grain, and without which there 

 would ha\'e been no mites. On the other hand, when drawn from 

 the field and placed unthreshed in the barn, the damage from this 

 pest has varied up to nearly fifty per cent., and has so affected 

 the crop as to cause its rejection by millers, except where ground 

 on the farmer's order. Here, then, lies the protection of people 

 who use mattresses made of this wheat straw, grown in this sec- 

 tion of the country, or otherwise come in contact with the same. 

 Reiterating in a condensed statement: Wheat should be 

 threshed immediately after har\-est and directly from the field. 



In Ohio, Indiana and Illinois, where the mite causing this der- 

 matitis has increased enormously on account of the prevalence 

 of the joint worm, see Plate V, fig. 3, wheat also placed in barn 

 before threshing has been found to be much more dangerous to 

 handle with reference to epidemics of this disorder. At the 

 same time, the difference between wheat threshed in the field and 

 in the barn is not so striking as where the ])rimary trouble was 

 in the abundance of the grain moth. 



A careful study of a large numl^er of wheat fields in central 

 Ohio, has shown that the infestation from joint worm, the present 



