DAY-FLYING MOTHS. 201 



Migration of Day-Flying Moths. 



Remark the habit of these day-flying moths of per- 

 forming migrations. The very beautiful Urania fulgens 

 migrates annually, from east to west, in August and 

 September, across the Isthmus of Panama. Flights 

 have been observed by a naturalist in the Isle of Caripi, 

 near Para in the Brazils, at Pernambuco, at Rio Janeiro, 

 and in the Southern States of America ; but he saw them 

 nowhere so abundant as on the Amazons. From early 

 morning till nearly dark, the insects passed along the shore 

 in amazing numbers, but most numerously in the evening, 

 and mainly, from west to east. Swainson, speaking of 

 U. braziliensis, a species almost the exact counterpart of 

 U. leihis, describes having witnessed a host flying during 

 the whole of a morning in June past Aqua Fria 

 (Pernambuco), in a direction from north to south not 

 one deviating from this course, notwithstanding the 

 flowers that were growing around ; and though they 

 flew near the ground, they mounted over every tree or 

 other high object which lay in their path, and it was 

 impossible to capture a single specimen, so rapid was 

 their flight. For three or four days they continued to 

 pass in this manner. On the occasion of the flights 

 over the city of Panama, in some cases the insects are 

 attracted into houses by the light, so as to almost fill 



