17 



BROWN-TAIL RASH. 



The term "brown-tail rash" is well understood in eastern New 

 England at the present time, although a few years ago it was practically 

 unknown. The hairs of the brown-tail caterpillar are finely barbed 

 and brittle (see fig. 9), and where the caterpillar comes in contact with 

 the human skin these hairs enter the skin pores, break off, and cause a 



FIG. 9. Hairs of the caterpillar of the brown-tail moth, highly magni- 

 fied. (Adapted from Kirkland.) 



severe irritation. Indeed, it is not necessary for the caterpillar itself to 

 come in contact with the skin; at certain times of the year it seems as 

 though the hairs were actually floating about in the air. At the time 

 of the caterpillar's change of skin, and particularly at the time of the 

 spinning of the cocoon and the final change, certain of these hairs 



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