File:The American Museum journal (c1900-(1918)) (18161270141).jpg

Title: The American Museum journal
Identifier: americanmuseumjo17amer (find matches)
Year: c1900-(1918) (c190s)
Authors: American Museum of Natural History
Subjects: Natural history
Publisher: New York : American Museum of Natural History
Contributing Library: American Museum of Natural History Library
Digitizing Sponsor: Biodiversity Heritage Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
Autumn Migrations of Butterflies Bv HOW A KM) .1. SHANNON Witli i-t ii-ils iiiailf on Loim iliiriiiLC Auiriist anil Si-;)tfnibci', I'.IIO SYSTEMATIC studies of the sea- sonal migrations of insects have always been attended by difficul- ties which are sufficiently obvious. The elusivencss, when in full flight, of the subjects themselves, the difficulty of distinguishing a merely local movement from an extensive advance, as well as the wide geographical range of various species wdiich may be considered mi- gratory, so that it is impossible to dis- tinguish incoming travelers from the resident population—all these are drawbacks which have stood in the way of more definite information. There- fore it is not surprising that we have such fragmentary knowledge of the species which do migrate, as well as of the laws which govern them in their annual behavior. In fact, there is a large and impres- sive body of opinion which questions whether butterflies take part in sea- sonal movements with any real con- stancy and regularity in temperate North America, except in the case of the "monarch" (Atiosia plexippus), and the great sulphur" (Cotopsilia euhiile), which certainly move south in autumn and north in spring. In addi- tion to these, of course, there are the dispersal movements from the south in- volving certain butterflies and, more particularly, moths like the cotton moth (Aletia arf/illncea) and the velvet bean moth (Anticarsia gemmatilis), which SCAL£ or MILES JL O Al G I S I^ AND
Text Appearing After Image:
atla nti^ '^^. -Vo oa- I\ MONARCHS IN MIGRATION. <^«-*< MIGRATIONS OF GRAPTA. PYRAMEIIS, JUNONIA AND OTHER BUTTERFLIES. Autumn migrations of butterflies on Long Island. Fluctuation in numbers of migrating butterflies from day to day is apparently due to changes in wind direction, so largely also a controlling factor in the migration of birds. Migration is much more profuse along the Long Island coast on days when the wind is north or northwest 1 Article and illustrations copyrighted, 1917, by Howard J. Shannon. 33

Note About Images