i:.i; GYPSY AM) BROWN-TAIL MOTHS. [Jan. 



aiul white vesicles on the skin; Bomhii.r rubi i)roduced intense irrita- 

 tion, vesicles, some of which became pustular, and edema of the eye- 

 lids; Bomb;/. i i/m /v.s, pimples which became vesicular and afterwards 

 dried up: and Hoinhi/.r >// stria, great irritation, but no vesicles. In- 

 oculation with Ard'ui </ and Ar<ti<t rillica was followed by transient 

 irritation. Dasyelwia fmdilninda caused red patches, and vesicles re- 

 sembling chicken-pox. Other species were tried, but proved to be in- 

 nocuous. Thresh (16) calls attention to short hairs. ., ^ of an inch 

 long, and barbed throughout their entire length, but thinks that the 

 long hairs as well have nettling properties. He states that the long 

 hairs give an acid reaction when they come in contact with litmus. 

 Perhaps the most notorious of the "stinging" larvae is Cnethocampa 

 /li/i/iir/nn/iii, (lie processionary caterpillar of Europe. Its poisonous 

 properties were known to the ancients, as is shown by the fact that it 

 is mentioned in the Cornelian law. 1 Keller (8 and 9) investigated this 

 species, and found structures at the bases of the spines which he inter- 

 preted .-is poison glands. 



There is in the Philippine Islands a moth (Taragama igniflua)" which 

 resembles somewhat the brown-tail. Its nettling hairs were examined 

 by the author, and found to be almost identical with those of the latter 

 species, and capable of producing severe irritation. There were also 

 long, needle-shaped, hollow spines, which were filled with fluid. As they 

 were watched under the microscope the fluid rapidly evaporated, leav- 

 ing the spines empty. Although these spines were well adapted for pene- 

 tration, it was not determined whether they were instrumental in the 

 production of the dermatitis. The larvae of the lo moth (Automcris 

 io) also produce irritation of the skin when handled. There is an im- 

 mediate sensation of pain, similar in nature to that produced by the 

 sting of a bee. but much milder in degree. There is some reddening of 

 the skin, but the irritation is transient, and soon disappears. 



The larger portion of the work upon which the present paper is based 

 was done several years ago. when the moth first became prevalent in 

 I he suburbs to the north of Boston, but certain additional data have 

 been obtained more recently. In investigating the nature of this pecu- 

 liar skin eruption, the primary object was to determine by means of 

 experimentation just how the lesions are produced. My observations 

 confirm those of Fernald and Kirkland, that the dermatitis is produced 

 by the peculiar, short, barbed spines or "nellliim bail's" 3 of the cater- 

 pillar. These hairs when rubbed upon the skin produce a dermatitis, 

 but the other hairs of either the caterpillar or the moth produce no 



1 Kirliy nnil Spenec < 



''. \IiMin-. l.cpidnplera -if <V;].m M '_' ) . 



:l Sin-h is tin' de-ive nf protective speeiali/at ion shown in these peculiar elements 

 that tin- Icrin " liair " furnishes hut an iiiailr<|natr conception of tlirir character. On 

 the cronnd of homolosry. however, (lie term "hair" seems .jiMifiahle, am] the termi- 

 nology of I'Vrnahl and Kirkland as regards these elements will accordingly be fol- 

 lowed. 



