404 ENTOMOLOGICAL NEWS [Nov., '12 



had changed to lilac, the side spots darker; on July 22, in the 

 morning-, the eggs hatched, after a stage of about fourteen 

 and a half days. 



The young larvae are gregarious and have a curious habit 

 of traveling in lines, one behind the other, all following the 

 first. Soon after hatching four larvae were noticed thus mov- 

 ing along, all in touch with each other, and all obeying the 

 movements of the first. A portion of an apple leaf was placed 

 in the path of the latter ; it was climbed upon without hesita- 

 tion, tasted, refused and the leader moved on; the others, 

 after a slight hesitation followed without tasting the leaf, 

 thus accepting the decision of the first. The short column 

 moved on and acted in the same manner when a clover leaf 

 was placed in their path. Then a piece of the leaf of corn 

 was placed in the path. The leading caterpillar stopped and, 

 after tasting it several times, began to feed, the others soon 

 advancing and following his example; the line was then 

 broken. If a leading larva of a larger string of the ycung 

 caterpillars is made to travel in a circle, so that the line gradu- 

 ally becomes circular and finally a complete circle, all of th 

 larvae in touch with each other, (.hey will continue in this 

 condition for hours. I have observed this on several occasions. 

 The gregarious instinct is strong and, as in all social com- 

 munities of animals, there appears to be some altruism and 

 division of labor, rude though this may be. Later this instinct 

 is lost ; it probably has arisen from the fact that the colony of 

 young after hatching once had to search for its food. 



The caterpillars were confined and fed; when not feeding 

 they rested in irregular masses or stretched in rows, one be- 

 hind the other. The first molt began on July 30 and was gen- 

 eral on the following day; the larva is very short, its body 

 contracted just after the first ecdysis ; when in the second 

 stage the young larvae rested either in masses composed of 

 regular transverse rows or else in a single line as noted above. 

 When disturbed in this stage the anterior end of the body is 

 swept rapidly from side to side, or else the head is simply 

 turned to one side. The second molt occurred about August 15, 



