In the woods and woods edges of eastern North America from Quebec to Manitoba and south to Florida and Texas roams the Pearly Eye. Yet it is found in queer little colonies, sometimes miles apart, with none others in between. In such places each jealous male chooses a tree trunk he considers his own alone and chases all other males, and often other insects too, away. Sometimes two males will fight each other for a minute or more, flying up against each other like fighting roosters, the one who is knocked down most often finally flying away. This is called the “territorial instinct,” common also among birds and some animals.
Try to catch a Pearly Eye and it will flay away from you so quickly into the underbrush that it soon loses you and by the time you have arrived where it was last seen, it has quietly lit upon some tree trunk where it is perfectly camouflaged. It may even fly to the ground and crawl under trash or leaves, hiding so completely as to be almost impossible to find. The bright eyes on the underside of the hind wings may help in scaring birds.
The little yellowish-green caterpillar is an extraordinary looking creature with two bright red-tipped horns on the head that should scare most birds.