GIPSY MOTH AND BROWN-TAIL MOTH AND THEIR CONTROL. 11 
serious poisoning and severe irritation accompanied with external 
swelling 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, H’ntomophthora 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 
nature, the benefit derived from it is regulated largely by favorable 
or unfavorable weather conditions. This fungus sometimes works to 
a slight degree on the small caterpillars in the fall, and in some 
instances 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 pup 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, Calosoma sycophanta, and its larve do valuable 
work each year in destroying brown-tail caterpillars and pupe, and 
the dipterous and hymenopterous parasites also attack this species in 
considerable numbers. Another imported parasite, namely, J/eteorus 
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. 
