71 



It is produced about six in the evening, and dies about 

 eleven, But before it becomes a fly, it exists three 

 years as a worm in a clay case. It never eats from the 

 time of its change to its death, n )r has any organs for 

 receiving or digesting food. Tae business of its life is 

 summed up in a few words ; as soon as it has drop* its 

 clay coat, the poor little animal being now light and 

 agile, spends the rest of its short-winged state in frisk- 

 ing over the waters. During this the female being im- 

 pregnated, drops her eggs upon the water; these sink 

 to the bottom, where they are hatched by the heat of 

 the sun into little worms, which make themselves cases 

 in the clay, and feed on the same or on what the 

 waters afford, without any need of parental care. 

 Thus they are inhabitants of the water, ,till the time 

 comes for shaking olf their shell, aad emerging into 

 air. 



Of one sort of ephemcron, Mr. Collinson writes 

 thus : May 26, 1744. 1 was first shewn this by the 

 name of May-fly. It lies all the year, but a few days, 

 at the bottom of the river, then rises to the surface of 

 the water,and splitting pen its case, up springs the new 

 animal, with a slenJer body, four shining wings, and 

 three long hairs in its tail. It next flies abouAo find 

 a proper place, where it may wait for its approaching 

 change. Tiiis comes in two or three days. I held one 

 on my finger while it performed this great work. It 

 was surprising to see how easily its back split and pro- 

 duced the new birth, which leaves head, body, wings, 

 legs, and even its three-haired tail behind, or the cases 

 of them. After it has rested a little, it flies nimbly to 

 seek its u.ate. The males keep under the trees remote 

 from th<; nver. Hither the females resorted, and when 

 impregnated, soon lef? the males, sought the rivers, 

 and kept^ continually playing up and down on the 

 Every tune they darted down they ejected a 

 cluster of eggs; they then sprang up again. Thus 

 they went up and down till they had exhausted their 

 stock of eggs, and spent their strength, being so weak 

 that they can rise uo more, but i'all a prey to the fish. 



