GIPSY MOTH AND BROWN-TAIL MOTH AND THEIR CONTROL. 11 



serious poisoning and severe irritation accompanied with external 

 swelling 1 and is known as the brown-tail rash. There is considerable 

 difference in the susceptibility of persons to this poison, but many 

 cases are reported each year in the infested region, most of which 

 are more serious than those of ivy 'poisoning. Many camps and sum- 

 mer cottages, particularly in wooded areas, can not be occupied with 

 any comfort during the early summer on account of the poisoning 

 resulting from these caterpillars. If clothing is hung on the line near 

 badly infested trees the hairs frequently find lodgment and are 

 brought into the houses, and later severe poisoning may result. 



NATURAL ENEMIES. 



One of the most important natural enemies of the brown-tail moth 

 is a fungous disease, Entomophthora aulicw, which attacks the cater- 

 pillars, particularly in the spring. It was first reported in this 

 country by Dr. Roland Thaxter in 1888. Like all diseases of this 



ire, the benefit derived from it is regulated largely by favorable 

 mfavorable weather conditions. This fungus sometimes works to 

 light degree on the small caterpillars in the fall, and in some 

 ances it is found in the winter webs. As a rule, however, the 

 greatest mortality of caterpillars takes place in the spring, when 

 they are nearly full-grown, and the pupse of the moth may, under 

 the most favorable conditions, be almost completely exterminated. 

 Native parasites and predaceous insects have done very little to check 

 the increase of the brown-tail moth. 



INTRODUCED PARASITES AND ENEMIES. 



The parasites and enemies already mentioned as being particularly 

 valuable for their work in destroying the gipsy moth also attack 

 the brown-tail moth, with the exception of the egg parasites. The 

 Calosoma beetle, Ccdosoma sycophanta, and its larvae do valuable 

 work each year in destroying brown-tail caterpillars and pupae, and 

 the dipterous and hymenopterous parasites also attack this species in 

 considerable numbers. Another imported parasite, namely, Meteorus 

 versicolor Wesm., has become established in this country and is doing 

 good work. It attacks the brown-tail moth caterpillars, but not 

 those of the gipsy moth. 



In some parts of the infested territory where some of the first 

 parasite liberations were made a marked decrease in the number of 

 moths has been noted during the past two years. The work of the 

 parasites will undoubtedly be more pronounced after they have 

 become more abundant over the entire infested territory. 





