ACADIA An Old Account of Mt. Washington A Word Upon its Insect Life A Word on Mt. Katahdin Sieur de Monts Publications XVIII

A GLANCE AT THE INSECTS OF MT. WASHINGTON AND MOUNT DESERT
CHARLES W. JOHNSON.
Curator of the Museum, Boston Society of Natural History.

Mt. Washington has long been a favorite collecting ground for entomologists. Here, in a limited area, one can study the many conditions governing distribution. Traveling from the base to the summit one passes in a short time through surroundings representative of the temperate, boreal and arctic climates. The vegetation on and around the mountain is practically undisturbed, presenting admirable facilities for studying the natural conditions governing the relative abundance of injurious and beneficial insects. We find the forests as a whole in a splendid condition, with no serious destruction by insects. The collecting that has been already done shows that here "nature's balance" has not been disturbed by the inroads of civilization. Moths, saw-flies, wood borers and other injurious species, while fairly abundant, are apparently kept within bounds by the great host of ichneumon and tachinid flies and other parasitic and predaceous insects. In fact, the abundance of beneficial species in proportion to the injurious ones is very noticeable, contrasted with other localities. Will not these large reservations in the near future furnish a most favorable place to study more fully the great economic problems of parasitism?

The upper portion of Mt. Washington is divided into two zones or areas, the alpine comprising the summit and parts above 5000 ft., and the sub-alpine, that from the timber line (about 4000 ft.) to the 5000 ft. contour. In the alpine area is found the White Mountain butterfly (Qeneis semidea) described by Thomas Say in 1828. This interesting butterfly belongs to a genus confined exclusively to the arctic and alpine regions.

1 Nepytia canosaria Mt. Desert 2 Argynnis atlantis Mt. Washington 3 Metanema determinata Mt. Desert 4 Œneis semidea Mt. Washington 5 Caripeta divisata Mt. Desert 6 Brenthis montinus Mt. Washington 7 Eustroma explanata Mt. Desert 8 Basilarchia arthemis Mt. Washington 9 Diastictis anataria Mt. Desert 10 Polygonia faunus Mt. Washington 11 Alcis sulphuraria Mt. Desert 12 Polygonia faunus Mt. Washington

The under side of the wings so closely resembles the moss covered rocks that when the insects are at rest they are scarcely discernible. Two little moths, Anartas melanopa and A. schoenherri, which frequent the rocky area, are also interesting examples of protective coloration. Under stones is found the large predaceous ground beetle, Carabus chamissonis. This species has also been captured on Mt. Desert. In the sub-alpine area are found the White Mountain Fritillary (Brenthis montinus) and the wingless grasshopper (Podisma glacialis). Generally distributed, but really living below the timber line, are numerous butterflies, including The Mountain Silver-spot (Argynnis atlantis), the Faun Angle-wing (Polygonia faunus) and the rare P. gracilis, Milbert's Tortoise-shell (Aglais milberti), and the Banded Purple (Basilarchia arthemis.) A full account of these is given in Scudder's "Butterflies of the Eastern United States."

On warm days, when a strong breeze is blowing up the sides of the mountain, numbers of insects are carried to the summit, making it a most interesting collecting ground. It was here that Mrs. Annie T. Slosson made a remarkable collection of over 2000 species. A revised list of the insects of Mt. Washington is in course of preparation by the writer.

The insect fauna of Mt. Desert has been only partially studied, but the list contains many species common to Mt. Washington. The late Dr. Charles Sedgwick Minot made a most interesting collection of over 100 species of moths at Northeast Harbor during his last summer there. The collection contained several new Geometrids (Span-worms) and a number of species not recorded from the eastern United States since Packard published his monograph in 1876. There were also many rare and interesting Noctuids (Owlet moths.) This collection and the interesting flora of the island would indicate a rich and varied insect fauna, deserving careful and systematic study.