INSECTS AT SEA. 85 



the supposition that the insects had been involuntarily 

 blown off the land was inadmissible.* 



But in these cases the land was not beyond the range 

 of moderate flight. What shaU. we say to jauuts of five 

 hundred or a thousand miles performed by these filmy- 

 winged and delicate creatures ? Mr Davis has recorded f 

 that a large dragon-fly, of the genus ^shna, flew on 

 board the ship in which he was sailing, on the 1 1th of 

 December 1837, when out at sea, the nearest land being 

 the coast of Africa, which was distant five hundred 

 miles. 



The late Mr Newport, in his Presidential Address to 

 the Entomological Society of London, for the year 1 845, 

 thus alluded to two other instances of the same interest- 

 ing phenomenon : — " Mr Saunders exhibited, at our De- 

 cember meeting, a specimen of JEshna, that was taken at 

 sea by our corresponding member, Mr Stephenson, in his 

 voyage from this country to New Zealand, last year. 

 This insect is a recognised African species, and was 

 captured on the Atlantic, more than six hundred miles in 

 a direct line from land. In all probability it had been 

 driven across the ocean by the trade winds, which blow 

 continuously at that season of the year in a direction 

 oblique to the course of the ship that was conveying Mr 

 Stephenson outwards. The other instance that has just 

 come to my knowledge is mentioned in a letter from Mr 

 Dyson to Mr Cuming. Mr Dyson states, that while at sea> 

 in October last, when about six hundred miles from the 

 * Nat. Voy., chap. viiL f Entom. Mag., v. p. 251. 



