84 HALF HOURS WITH INSECTS. [Packard. 



hairs from its body and dextrously weaving them into a firm 

 texture without the aid of silken threads, the hairs being 

 held firmly in place by the barbs. 



"June 13th, the Ctenucha larva began to construct its co- 

 coon. Early in the morning it described an ellipse, upon 

 the side of the glass vessel, of hairs plucked from just behind 

 the head. From this elliptical line as a base, it had by eight 

 o'clock built up rather unequally the wall of its cocoon, in 

 some places a third of the distance up, by simply piling upon 

 each other the spinulated hairs, which adhered firmly to- 

 gether. At four o'clock in the afternoon, the arch was com- 

 pleted and the larva walled in by a light thin partition. 

 Soon afterwards the thin floor was made. No silk is spun 

 throughout the whole operation. I afterwards carefully ex- 

 amined portions of the cocoon under the microscope and 

 could detect no threads of any kind." 



From this it will appear that aside from their defensive 

 nature, these barbed hairs come into play when the insect 

 prepares to lay aside its caterpillar skin like an old garment, 

 and go into retirement as a chrj^salis. So also the hairs of 

 the "woolly bear" caterpillar {Arctia Isabella) and of the 

 common Vanessa butterfly ( Vanessa Antiopa) are poisonous 

 to children. 



The caterpillar of another moth, the Emi^'etla stimulea, is 

 said by Dr. Clemens to be very annoying. "The spines with 

 which the horns are supplied produce an exceedingly painful 

 sensation when they come in contact with the back of the 

 hand or any portion of the body in which the skin is thin." 



The caterpillar of the lo moth {Tlypercheiria lo, Fig. G4 ; 



65 a, 6, c, spines), which feeds commonly on corn in the 

 southern states, though in New England it feeds on the 

 maple, is covered with stinging hairs, which are often pain- 

 ful when detached. 



The caterpillar of the Maia moth (Hemileuca Maia, Fig. 



66 a, caterpillar) is armed with still more annoying spines. 



20 



