140 LIBELLULTDiE — DRAGON-FLIES. 



rivers, with the currents. They did not, however, always 

 keep close by them, since they must spread over wide dis- 

 tricts in order to subsist. 



To account for the great multiplication of these insects, in 

 the year 1839, is by no means difficult. From the beginning 

 to the 21st of May (in the latter part of which month, it will 

 be remembered, they appeared), the weather had been ex- 

 ceedingly rainy ; rivers and lakes overflowed their banks 

 and inundated immense areas of low grounds, whereby 

 myriads of the larvae and jyupse (which live entirely in 

 water) of the Lihtdlulse, which, under other circumstances, 

 would have remained in deep water, and become the prey of 

 their many enemies, fish, etc., were brought into shallow 

 water, and hot weather following, from May 21st to May 

 29th, converted these shallows and swamps into true hot- 

 beds for them. Their development into perfect insects was 

 thus rendered rapid, so that, somewhat earlier than usual, 

 they appeared, and in far greater, their undiminished, num- 

 bers ; and, being very voracious in their appetite, as well in 

 the imago as the pupa state, they were obliged to migrate 

 immediately to satisfy it.^ 



Mr. Gosse observed in Jamaica, Oct. 8th, 1845, a swarm 

 of Dragon- flies in the air, about twenty feet from the level 

 of the ground. They floated and danced about, over the 

 stream of water that runs through Blue-fields, much in the 

 manner of gnats, which they resembled also in their immense 

 numbers.^ And Rev. T. J. Bowen, on one occasion, in de- 

 scending the Ogun Biver (in the Yoruba country, Africa), 

 met millions of Dragon-flies, about one-fourth of an inch in 

 length, making their way up the country by following the 

 course of the stream.^ 



It is commonly said among us, that if a Dragon-fly be 

 killed, there will soon be a death in the family of the killer. 



1 Mag. of Nat. Hist., iii. 51G-8. 

 '^ Gosse's Jamaica, p. 251. 



3 Gram, and Diet, of the Yoruba Language Smitlison. Public, 

 p. xiii. 



