( v ) 



" A few stragglers belonging to other species were seen with 

 the main stream, but the only one I was able to recognise was 

 Danais chrysippus, while, beyond the fact that those other 

 species were flying in the same direction when I saw them, 

 there is no evidence that they were migrants. 



" I do not know if migrations of this species are of common 

 occurrence in Africa, but I am told that migratory swarms 

 of butterflies are rare at Freetown, though my boy, a native 

 from further south (Lagos), told me that in his country 

 butterfly migrations are of annual occurrence. The Creole 

 population of Sierra Leone, I was informed, considered the 

 phenomenon a portent boding ill to the colony. 



" Subsequent to the first migration, several small flights 

 of the same insect were seen in the adjacent country. 

 They passed without notice or comment by the general popu- 

 lation. It would appear, therefore, that the numbers alone 

 were the remarkable feature of the first migration. 



" During the previous September there was an immigration 

 of a Vanessid closely allied to Pyrantels cardui, possibly only 

 a local variety, into Freetown and the surrounding district. 

 These insects I first saw in large numbers in the centre of the 

 town, on Tower Hill, flying in the dusk like swift moths. They 

 haunted Tower Hill alone for a few days, and then became 

 generally dispersed through the town and district, although 

 always most numerous on the hill where I first saw them. 

 As the days passed they seemed to lose the marked habit of 

 flying in the dusk. I saw numbers paired and at rest about 

 dusk. They died out completely in about five or six weeks, 

 and no breeding occurred, presumably owing to the lack of a 

 suitable food-plant." 



Commander Walker, Mr. J. C. F. Fryer and Dr. Cockayne 

 commented on the migration of butterflies. 



Cross breeding of Pediculus capitis and P. humanus. — 

 Mr. Bacot also exhibited a box containing recently hatched 

 lice resulting from a pairing between Pediculus captitis, o, 

 and P. humanus (vestimenti), $, and remarked that there was 

 no difficulty in obtaining pairings between the two insects, 

 in either direction; a state of affairs which was unusual in 

 his experience of cross-pairing different species. It seemed 



