Life History and Habits of Two Pacific Coast Bark Beetles.*

For many years two species of engraver beetles have been doing considerable injury to Monterey pine (Pinus radiata Doug.) along the central part of the California coast region. These two species are very similar in appearance and habits, and at first, both were included under the name of Ips Plastographus Lec., a species described by J. L. Leconte in 1868. For a long time, however, it was known that two species were represented, and that these could be readily distinguished by the character of the larval mines. They could also be less readily separated by the arrangement of the spines on the posterior declivity, and by the punctures on the elytra.