THE COMMON EPHEMERA OR DAY-FLY. 345 



once observed. The most unobserving of my do- 

 mestics could scarcely ever have been tired of ad- 

 miring it. No astronomic sphere was ever formed 

 so complicated as it was, nor furnished with so 

 manycircular zones in every possible direction, hav- 

 ing the flame of the candle for their common cen- 

 tre. Their number appeared to be infinite, havinsr 



o 



all possible degrees of obliquity with respect to 

 each other. Each zone was formed by an uninter- 

 rupted string of Ephemerae, which, as if tied toge- 

 ther, followed each other close in the same line ; 

 they seemed to form a circular ribbon of silver, 

 deeply indented on its edges ; a ribbon formed of 

 equal triangles put end to end, so that the angles of 

 those that followed w T ere supported by the base of 

 that which preceded, the whole moving round with 

 great quickness. Ephemeras, whose wings only 

 were then distinguishable, and which circulated 

 around the light, formed this appearance. Each of 

 these flies, after having described one or two orbits, 

 fell to the earth, or into the water, but without hav- 

 ing been burned by the candle." At the end of 

 about half an hour from its commencement, the 

 great shower began to abate, and in little more 

 than an hour scarcely any Ephemeras could be seen 

 above the river, and no more came near the candle. 

 This phenomenon M. de Reaumur found, upon 

 examination, took place every evening, commenc- 

 ing usually about the same hour, during most of the 

 summer months. 



In this short period of existence, the female ap- 

 pears to have no other business than to lay her eggs. 



