THE BIiOW\-TAlL MOTH. 37 



Dr. O. A. Gibson, 22 Summer Street, Somorville, 

 writes : — 



The first we saw of these moths was in 1897. The first cases 

 of poisoning I saw were on Sprhig Hill Road and Park Street. 

 I saw a number of cases, and they were all about the same, except 

 that they varied in point of severity. Some of the cases were very 

 obstinate, and did not respond well to treatment. The same symp- 

 toms developed in nearly all cases. The trouble began with an 

 intense irritation ; then an eruption appeared, resembling eczema, 

 with a sort of a watery blister on the top. There was intense irri- 

 tation all over the bod}', on the head, arms and limbs. I saw 

 numbers and numbers of cases of this poisoning ; I should say 

 nearly a hundred cases in all came under my observation. The 

 irritation seemed to remain, and was much worse than that caused 

 by poison oak or poison ivy, and was not so easily gotten rid of. 

 I treated most cases with some cooling application. Some cases 

 were decidedly obstinate, but no case Avas serious enough to menace 

 the life of the patient. 



Tlie CJiemistry of it. 



A great deal has been written in European works about 

 the nettling properties of the brown-tail moth, and various 

 conjectures made as to the cause of the trouble ; but the 

 general consensus of opinion seems to be that the nettling 

 is caused by a poisonous substance in or on the finely broken 

 hairs of the larvfe, coming in contact with the skin. Many 

 also believe the cocoon to be even more troublesome than 

 the larvfB. In an article in "The Entomologist," Vol. 17, 

 p. 276, 1884, written from Chichester, Eng., it is stated 

 that the moths of this species possess this stinging property, 

 and the opinion is cx})ressed that the irritation is caused by 

 the white hairs that frinije the inner margins of the wimjs. 



Mr. C. G. Barrett, in his excellent work on the " Lepi- 

 doptera of the British Islands," Vol. TL, p. 21)4, 1895, writes 

 as follows : — 



With the silk composing the cocoon are intei'woven the hairs of 

 the larva, which becomes brittle, and, when the bush or hedge is 

 disturbed, are thrown out as a fine dust, which, sticking to the 

 skin of the liands, face or neck of a passerby, causes an intense 

 irritation, with infiammation which closely resembles nettle-rash. 

 It is on record that a thick hawthorn hedge upon which larva' and 



