Ephemera, the May -Fly, 151 



Aristotle, speaks of the same insect under the name of Mone- 

 meron.* Scaliger, in his commentary on Aristotle's History of 

 Animals, remarks that numbers of Ephemeras are occasionally 

 observed flying about the Garonne and Tarn, where they are 

 commonly known by the name of Manna, from the fact of their 

 forming an abundant food for the fish. Moufet, in 1634, 

 speaks of certain genera of Ephemeras, which possess two 

 caudal setas only, under the name of Dittotriches {hiTTOTpc^es)^. 

 But none of these writers appear to have given much attention 

 to the natural history of this interesting family of Neuropterous 

 insects. It was reserved for the illustrious Dutch naturalist, 

 Swammerdam, to make known to the world most of the wonders 

 of ephemeral life. His observations have, for the most part, 

 been verified by Reaumur and De Geer (1742 and 1745) ; Sco- 

 poli, Kirby, Burmeister, Stephens, and Pictet, are names well 

 known to all engaged in the study of the Epherneridas. 



In our own country, the May-flies appear about the end of 

 May and the beginning of June, and continue for about three 

 weeks. The green-drake issues from his nymphal state almost 

 at any hour in the day, but especially when the sun is shining. 

 In Sweden, the birth of these insects is confined nearly to the 

 evening, about sunset ; but it is quite an error to assert that 

 our British Eph. vulgata emerges from the water only in the 

 eveniug.J Some species of Epherneridas appear in the most 

 astonishing swarms, in some parts of Europe. Scopoli tells 

 us, that so great an abundance of Eph. vulgata sometimes 

 occurs near the Lake Laz, in the month of June, that the 

 inhabitants of the district are quite disappointed if they do not 

 collect twenty cartloads of insects for manure ! " Between the 

 10th and 15th of August is the time when those of the Seine 

 and the Marne, which Reaumur described, are expected by the 

 fishermen, who call them manna; and when their season is 

 come, they say, " The manna begins to appear ; the manna fell 

 abundantly such a night" — alluding, by this expression, either 

 to the astonishing quantity of food which the Ephemeras afford 

 the fish, or to the large quantity of fish which they then take." 

 These immense swarms of Epherneridas have been noticed in 

 Holland, Switzerland, and France, and have been compared to 

 falling flakes of snow. " The myriads of Ephemera which 

 filled the air," says Reaumur, " over the current of the river, 

 and over the bank on which I stood, are neither to be expressed 

 nor conceived. When the snow falls with the largest flakes, 

 and with the least interval between them, the air is not so full 

 of them as that which surrounded the Ephemeras." The 



* From fx6vos, " alone," or " single," and yftepa, " a day." 



t That is, " two tails," or " hairs." 



% W. S. Dallas in Orr's Circle of the Sciences, Organ. Nat. ii., p. 365. 



