Page:The Scientific Monthly vol. 3.djvu/236

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230 THE SCIENTIFIC MONTHLY

and eastern Texas that they probably represent a mingling of various streams from Manitoba, the farther Canadian territory, and even from the northern shores of Lake Superior where a flight-line probably trends west only to turn south after passing the lake's extremity. The result is shown in gatherings of almost unbelievable magnitude. For here, unobstructed by barriers of lake, or ocean or mountain height, such as in other regions deflect and crowd the travelers into single-file processions, the mingled myriads move forward in broader, freer swarms that mount high, forming veritable crimson clouds; and in these im- pressive congregations — miles in width and streaming backward for equal distances — the crowding, ever-fluttering wings press onward to- ward the south, casting below them as they go perceptible shadows that move in company with the brilliant travelers in flight above the sunlit plains.

Vast aerial armies of dragonflies also advance along certain of the

���/•/f/IA/if/f lAC£jf/tT/[ L/BELLULA PULCHELLA, GREAT SULPHUK

BUTTE^rLY

PiQ. 2. Some Littijs Known Migrants op North America. These two Inter- esting dragonflies have never before been reported in migration. The great sulphur, being a Southern butterfly, does not often reach the latitude of New York in any great numbers.

highways, although the scattered and broken processions are the usual mode of travel. Moreover, by using the routes already determined as a key, further confirmations are obtained regarding the seasonal char- acter of their migrations in the manner of birds. For not only does the common Long Island migrant, Anax Junius, travel southward along the Jersey shore, as sho\%Ti by Wolff's September observation at Cape May, but also this same species travels westward along the Connecticut shore of the Sound as shown by the writer's August and September observa- tions.

Then, too, a report of resting swarms, appearing at Point Pelee (the butterfly route already defined), would seem to show that A?iaa: also follows our second great highway along I^akes Erie and Ontario. In fact, still further observations by the same observer, Mr. F. M. Root, show that eight other kinds of dragons, as w^ell, appear at the point in late summer; and, as some s})ecies are less profuse in the earlier season, they are apparently migrating to another region. Among them are

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