51 G MIGRATION OF DRAGON-FLIES 



es began, so they might end with, and his bones rest on, the 

 oolite ; and it is rather remarkable that this wish is realised 

 in our church-yard (St. Peter's), where the Professor and I 

 followed his remains on the Monday after his decease 1 '. — 

 (Addressed to the Editor, and dated Northampton, Sept. 23, 

 1839). 



Great Migration of Dragon-flies observed in Germany. — 

 On the 30th and 31st of last May immense cloud-like swarms 

 of dragon-flies passed in rapid succession over the town of 

 Weimar and its neighbourhood. The general direction of the 

 migration was from South by West to North by East. The 

 migration had been likewise observed in all the villages situ- 

 ated a few miles to the east or west. The insects arrived in 

 a vigorous state, some of the flocks flying as high as 150 feet 

 above the level of the river Ilm, and striking against the win- 

 dows of a house situated on an eminence ; others passing* 

 through the streets. The specimens caught there were those 

 of Libellula depressa, at least, all that I have seen were of 

 that species. 



Being anxious to ascertain the range of this migration, I 

 tried to collect every possible information from various pa- 

 pers, but all I could learn from that source was, that cloud- 

 like swarms of dragon-flies had been seen at Gottingen on 

 the 1st of June, at Eisenach on the 30th and 31st of May 

 (flying from East to West), and at Calais on the 14th of June, 

 on their way towards the Netherlands. Those seen at Eis- 

 enach were likewise Libellula depressa ; those observed at 

 Calais appeared to belong to a different species, as they were 

 described as being thick, and about 3 inches long. 



Being rather disappointed in my expectation of finding 

 news from many quarters respecting the same phenomenon, 

 I endeavoured to procure more information by means of a 

 public advertisement; whereby I learned that the swarms of 

 dragon-flies had been seen about the same time as they were 

 here, in the neighbourhoods of Leipzig, Alsleben, Aschersle- 

 ben, and Halle. The information which Dr. Buhle, the in- 

 spector of the Zoological Museum of Halle, had the kindness 

 to impart, was particularly valuable. The specimens caught 

 at that place belong to Libellula qiiadrimaculata. The first 

 swarms arrived there in the afternoon of the 30th of May, a 

 short time before a thunder-storm. 1 They flew very rapidly 

 from South to North. On the 31st of May similar flocks fol- 

 lowed their predecessors in the same direction ; most of them 



1 1 see from my meteorological journal that we had a thunder-storm here 

 hoth on the 30th and the 31st of May, and two on the 1st of June. 



