CHAPTER V 
THE MAY-FLIES (Order Ephemerida) and STONE- 
FLIES (Order Plecoptera) 
AY-FLIES, lake-flies, or shad-flies, common names for 
the insects of the order Ephemerida, are familiar to 
people who live on the shores of lakes or large rivers, 
but are among the unknown insects to most high-and- 
dry dwellers. 
Travelling down the St. Lawrence River from 
Lake Ontario to Quebec one summer, I had hosts of 
day-long companions in little May-flies that clung to 
my clothing or walked totteringly across my open book. The summer 
residents of the Thousand Islands get tired of this too-constant com¬ 
panionship, and look resentfully on the feeble shad-fly as an insect pest. 
One evening in August, 1897, m y attention, with that of other strollers along 
the shore promenade at Lucerne, was called to a dense, whirling, tossing 
haze about a large arc light suspended in front of the great Schweizerhof. 
Scores of thousands of May-flies, just issued from the still lake, were in 
violent circling flight about the blinding light, while other thousands were 
steadily dropping, dying or dead, from the dancing swarm to the ground. 
Similar sights are familiar in summer-time in this country about the lights 
of bridges, or lake piers and shore roads. This flying dance is the most 
conspicuous event in the life of the fully developed, winged May-fly, and 
indeed makes up nearly all of it. With most species of May-flies the winged 
adult lives but a few hours. In the early twilight the young May-fly floats 
from the bottom of the lake to the surface, or crawls up on the bank, the 
skin splits, the fly comes forth full-fledged, joins its thousands of issuing 
companions, whirls and dances, mates, drops its masses of Vggs on to the 
the lake’s surface, and soon flutters and falls after the eggs. It takes no 
food, and dies without seeing a sunrise. Sometimes the winds carry dense 
clouds of May-flies inland, and their bodies are scattered through the streets 
of lakeside villages, or in the fields and woods. Sometimes the great swarms 
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