This is a part of the report of a commission that has been of immense service to American science. In this, Mr. Grote gives a full account of the new Zimmerman Pine Pest, Pinipestis Zimmermanii, a very destructive insect to the red and white Pines. Besides these natives, it attacks the Scotch and Austrian imported Pines. "The wounds occur on its main stem, usually below the insertion of a branch. On cutting into the bark beneath the exuding pitch, the larva may be found, which measures about eighteen millimetres when full grown. The head is shining Chestnut brown, with black mandibles. The body is livid or blackish green, marked with series of black dots, each giving rise to a single bristle. The prothoraic shield is blackish. The larva has three pair of thoracie or true-jointed feet, and four abdominal or false feet, besides anal claspers. This larva, eating on the inner side of the bark, and making furrows in the wood, causes the bleeding, which, when the depletion is excessive or continuous, and especially in the case of young trees, has proved fatal." Pinipestis Zimmermanii seems to be one of the most destructive of Lepidopterous insects to timber.

I have seen a number of young Pine trees killed by it".