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ingenious Friend Mr. Bartram , excited him to 
make the following Remarks on their Appearance in 
Benfyfaania. By the Specimens before you, the 
May-flies of America have no very remarkable Dif- 
ference from ours excepting a few Days in the Fly 
State, they live all theYear aWater Infeft. Their Bodies 
being replenifhcd with an oily Matter, they eafily 
quit their Husks, and rife up to the Surface of the 
Water, and difperfe themfelves a Mile or more back 
in the Woods, whilft others flay near the Wa f er. 
May the 4th 1749. I perceived many had attained 
Wings, and were very thick fpread on the Bufhes and 
Grafs, by the River-iides. The fecond Day after 
their leaving their aquatic Abode they call another 
Skin, after which their Tails are longer, and their 
Wings drier, and more tranfparcnt. The yth and 
6th was rainy, the 7th windy 5 fo very few came our. 
The 8th were cool; fo few were feen : But the pth 
and 10th, being warm, many fwarmed late in the 
Evening; and the nth, 12th, 13th, they fwarmed 
abundantly. What I call fwarming, was their gather- 
ing thick as Bees, near the Rivers, to lay their Eggs 
in the Water. 
In their Flight they mount to the Tops of Trees, 
20 or 30 Feet high : Their Motion is furprifing, 
hovering up and down, rifing and falling, 7 or 8 
Feet at a time : This I take to be the Time and Man- 
ner of their Impregnation. After which they fly 
to the Brooks, call out their Eggs, and perifh im- 
mediately : Their Eggs fink directly to the Bottom, 
and lodge amongft the Mud and Gravel, and may be 
Food for fome minute Water Animal. From their 
Eggs proceeds a deformed Grub, which fublifts under 
Water, 
