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many parts of France, Bavaria, Switzerland, Austria, etc. 

 Thus we find that in Wiirttemburg from the ist to 8th 

 there was incessant migration from south and west to north- 

 east and east. At Zurich on the 7th an immense swarm 

 moved from south-west to north-east, their flight being per- 

 sistently in one direction. At Wettsweil, on the same day, 

 a swarm flew from west to east, and it is calculated that at 

 least 11,000 passed the observer. In Upper Austria, on the 

 nth, surprising numbers passed from south-west to north-east 

 ceaselessly ; between i and 2 p.m., ninety to a hundred per 

 minute were counted in a breadth of 100 paces. Near 

 Geneva a swarm is said to have obscured the sun for several 

 minutes. At Strasbourg, from the 3rd to 9th, great swarms 

 appeared flying towards the north ; while at Sevres, near 

 Paris, a similar occurrence was noted on the 15th, the direc- 

 tion taken being from S.S.E. to N.N.W., the wind at the 

 time being S.S.W. At Angers, on the loth, myriads passed 

 from east to west, against the wind ; and at Rennes, on the 

 same day, vast numbers flew from south to north with great 

 rapidity, sometimes twenty to thirty passed in a minute, and 

 continued for some time at the same rate. Migratory swarms 

 were not noted in North Germany or Belgium, but the insect 

 was excessively common in the latter country. Returning to 

 this country, we find that this species was not particularly 

 common during the previous autumn or early spring months 

 of this year ; it was somewhat more plentiful in May ; but it 

 was not until June loth that it was observed in great abun- 

 dance. On that date it appeared in the " utmost profusion " 

 {E.M.M. xvi. 99). This date is of importance, as it is un- 

 likely that hybernating specimens would have remained 

 quiescent until so late in the year, and it is equally im- 

 probable that spring broods would so soon have reached 

 maturity ; whereas, it fits in well with the time at which some 

 of the migratory columns were passing over the continent in 

 the direction of these islands ; they, however, appear to have 

 broken up on or before reaching our shores. Following on 

 this abundance of the imago, larvae were very abundant, 

 being found in considerable numbers right into the end of 

 October ; but they do not appear to have arrived at maturity, 

 and the species in the following year was even scarcer than 

 usual. It may be worthy of mention, as illustrating its 

 powers of flight, that a butterfly of this species was seen 

 sunning itself on the bare rocks in the Great Desert of Nefud, 

 Central Arabia, at least 400 miles from any place where the 

 larva could have fed up {E.M.M. xvi. 185). 



