VOL. XIII.] NOTES ON MIGRATION OF BIRDS. 175 



meeting in the longitude of Malta. Fig. i represents spring 

 migration in 1917 in the western area ; fig. 2 shows it in the 

 eastern area ; fig. 3 is a combination of the other two figs. 

 The western area of fig. i has as boundaries roughly a line from 

 Malta to Bizerta, from Bizerta to Marseilles passing seventy- 

 five miles east of Minorca, from Marseilles to Leghorn, down 

 the west coast of Italy, through the Straits of Messina to 

 Malta. The eastern area of fig. 2 is bounded by a line from 

 Malta to Messina, from Messina to Cape Matapan, from 

 Cape Matapan to Suda Bay near Khania in Crete, thence to 

 the African coast and then to Malta. Fig. 3 shows us that 

 there was a fairly steady stream of migrants from the end of 

 March to May loth. Then for a fortnight or more no migrants 



Ft G 4. Fig 5. 



AUTUMN MIGRATION I916. 

 Fig. 4. WESTERN AREA Fig. 5. EASTERN AREA. 



were seen, but at the end of May and beginning of June 

 there was another small migration in the eastern area if not 

 in the western. Fig. i shows us that the gap occurred in the 

 western area and suggests that migration northwards finished 

 in the western area before that in the eastern. Unlike what 

 occurred in the migration of the autumn of 1916, due to bad 

 weather, there was no bad weather to account for the gap 

 in May. 



Figs. 4 and 5 are charts of the autumn migration of 1916 ; 

 fig. 4 represents the western area, bounded by the longitude 

 of Marseilles, the longitude twenty miles east of Corsica, and 

 the European and African shores between them. Fig. 5 

 represents the eastern area, a strip about thirty miles wide 

 between Malta and Crete. These charts show us scanty 

 migration in September and the beginning of October ; after 



