18 



appear to become loosened in such a way that they are carried by the 

 wind. A few people have been made seriously ill by this so-called 

 rash, arid it is the cause of great annoyance. Extreme cases were 

 noted during the past summer in the parasite laboratory at North 

 Saugus. Two of the assistants who had charge of the American end 

 of the introduction of the European parasites of the gipsy moth and 

 brown-tail moth and were obliged to handle large numbers of the win- 

 tering nests brought over from Europe were poisoned to such an 

 extent that their hands and arms were swollen to great size, their eyes 

 were swollen nearly shut, and the irritation of the hairs in the throat 

 and nasal passages was such as to cause alarming symptoms. Begin- 

 ning with April, one of the assistants has had an almost constant cough 

 from this cause, lasting to the date of the present writing (August 30). 

 Persons engaged in removing the nests from trees in the winter time 

 and in carrying them away to be burned also suffer from brown- 

 tail rash, altho the trouble is not so great in the winter time as in the 

 summer time, since during warm weather the pores of the skin are 

 more open and more receptive to the hairs. A large part of the pop- 

 ular feeling in New England that the brown-tail moth must be exter- 

 minated is due quite as much to the prevalence and annoyance of this 

 rash as to the loss of vegetation from the work of the caterpillars. 



For a time the free use of vaseline was recommended for the 

 so-called brown-tail rash, but of late cooling mixtures have been used 

 in preference, and an excellent prescription which has been tried 

 repeatedly with good effect is the following: 



Menthol ." grains. . 10 



Zinc oxidi drams . . 2 



Aq. calcis ounces. . 8 



Acid carbolici drops.. 15 



This mixture is for external use. 



The hairs which produce the worst effect are the short brown ones 

 from the tubercles on the back and sides of the abdomen. They are 

 illustrated in fig. 9. This nettling or urticating effect is not pecu- 

 liar to the hairs of the brown-tail moth. A number of our native 

 species carry similar hairs. The difficulty is apparently purely a 

 mechanical one, and there is no accompanying specific poison. 



NATURAL ENEMIES AND PARASITES. 



Observations extending over a number of years show that birds are 

 important in checking the spread of the brown- tail moth. The cater- 

 pillars, like other hairy species, are not so much eaten by birds, except 

 by certain ones, such as the yellow-billed and black-billed cuckoos and 

 the Baltimore oriole. The yellow-throated vireo and the bluejay also 



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