198 THE entomologist's record. 



just hatched, which they obviously reject when middle-aged, I cannot 

 explain, but such really seems to be a fact. 



The partial double-broodedness of P. smaratjdaria seems to be now 

 an established fact. I reared several imagines, sleeved out of doors, on 

 A. absinthium, in August, 1899 ; two males on Achillea millefolium in 

 early September, 1900 ; and I find a note by Mr. H. J. Turner that a 

 larva taken by himself on August 31st, 1895, produced an imago (a 

 male) on October 10th of the same year [Entomoloiiisi' s Record, vol. vii., 

 P-82). =_=_= 



Migration and Dispersal of Insects : Lepidoptera. 



By J. W. TUTT, F.E.S. 

 The migration of the Callidryads is not confined to eastern lands. 

 In America they are still the most prominent of the migrating 

 species, and Scudder observes that they show a distinct propensity 

 for congregating together, even when not acting under a migratory 

 influence. Commenting on this Marchwood says that he has seen 

 quite a hundred specimens of Pierid butterflies within the diameter 

 of twelve inches. Lindley saw in Brazil, in March, 1803, an immense 

 flight of white and yellow butterflies which continued to pass 

 for many days successively in a south-easterly direction, whilst 

 Werneburg says that at Venezuela, on one occasion, in June or July, 

 " a throng of dift'erent species of Callidri/ades moved in a northerly 

 direction out to sea for many days together, between 11 a.m. and 

 2 p.m." Spence records the passage " of a vast multitude of butter- 

 flies of common white and orange-yellow species flying to the S.S.E. 

 across the Amazon at right angles to the wind," in November, 18-19. 

 He further states {Journal Linn. Sac, ZooL, ix., pp. 355-357) that, in 

 South America, the direction of the migrating swarms is mainly south, 

 and he considers them to be largely due to the exhaustion of the food- 

 supply in seasons when the insects are, by rain and other favouring 

 circumstances, produced in certain districts in unwonted abundance. 

 Willet states {Canadian Lntoniolu;iist, xii., p. 40) that at Macon, 

 Georgia, he saw " CalUdri/as cubulc passing in great numbers during 

 September, October, and November, 1878, from north-west to south- 

 east. About noon, when they were most abundant, there would be 

 half-a-dozen visible all the time cx'ossing a 15-acre square of the city. 

 They pursued an undeviating course, flying over and not around houses 

 and other obstructions. They flew near the ground and stopped 

 occasionally to sip at conspicuous flowers. Papers in southern Georgia 

 noticed the great numbers passing at different points, and a friend in 

 southern Alabama sent specimens of the same, saying that they were 

 subjects of speculation there. About March, 1879, there was a similar 

 migration from S.E. to N.W., but in diminished numVjers." He 

 further states that he saw the autumnal migrations again in October 

 and November, 1879, but in smaller numbers than in 1H78. He also 

 notes that a lady of S. Georgia informed him that her husband called 

 her attention to the autumnal migration twenty-six years ago, and that 

 she had observed it every year since. Gibber writes from Charleston 

 {loc. cit., xii., p. 60) : " In the course of the last two or three years 

 several accounts have appeared in Nature of flights of lepidoptera in 



large numbers In the summer (August) of 1870 I was 



crossing the harbour of this city by the 3 p.m. trip of the steam-packet 



