Many visitors to Crater Lake National Park during the past month have had their attention brought to the large number of butterflies flying in and through the park, and often becoming troublesome on the radiators of automobiles.

The California tortoise shell (Vanessa californica Behr.) is the name applied to the species which is most commonly seen. They may be seen in great numbers from the Transitional Zone to the highest points in the Hudsonian Zone where they are most common about moist places, but are often seen flying by the thousand in one direction, apparently heading for a definite place. The following day, or even later in the same day, they are found moving in the opposite direction. The larvae of this species feed on several of the wild shrubs of the mountains, and often do considerable damage in this way.