ON THE MIGRATION OF BIRDS. 13 



Europe resort to for a short period, or pass more or less regularly ; 

 from this they seem to continue their journey by the lakes of Mo- 

 rat, Neufchatel, and Bienne, and repair to the Rhine, the course of 

 which they follow, and thus arrive at the Baltic, the great inland, 

 and North Seas. These companies, already less numerous when 

 they arrive in the north, disperse themselves soon afterwards." At this 

 period, the individuals pair and attend to the wants of their new pro- 

 geny. The route most frequented by all the water-birds, is along the 

 borders of the sea : those which come from the Gulf of Gascony, from 

 Spain, and the coasts of Barbary, appear to follow that only ; several 

 species of waders follow it uniformly ; and the same route is taken by 

 all those birds which are unprovided with powerful means of flight. 

 The divers, the grebes, and other fresh water fowl, which seldom fly 

 when occupied with the cares of pair-ing and breeding, are, however, 

 endowed with great powers for this action ; their flight is vigorous and 

 long sustained ; they rise even above the high mountains, for it is not 

 rare to find individuals of these species on the lakes of the Alps, where 

 the waders and web-footed species are often killed. It appears that 

 the great flocks which assemble in the Ionian Isles, and the vast 

 marshes between Venice and Trieste, follow in their travels the course 

 of the Tagliamento, to arrive at the lakes in the environs of Villach 

 and Klagenfurt ; they visit the immense marshes which form the 

 lakes Balaton and Neuzidel, where several species remain, while others 

 reascend the Danube, and continue their journey to the Baltic Sea. On 

 the lakes of Hungary, and upon the Danube, several species are found, 

 which also visit the shores of the ocean. It appears to me, that the 

 species most peculiar to the western countries assemble in the Archi- 

 pelago, and on the borders of the Black Sea ; they reascend the Da- 

 nube, and following the course of the river, arrive in Hungary and 

 Austria, countries that abound with various species of birds in great 

 numbers. I have not travelled over the whole extent of country 

 crossed by the birds in the latter migration, nor that which takes 

 place from the Gulf of Lyons by the mouths of the Rhone, along that 

 river, and by the Doubs, the way by which their companions reach the 

 Rhine. The banks of this river are peopled in spring and autumn by 

 a great number of birds : we find in the part which forms the boundary 

 of the western countries of Germany, all the species which go by the 

 shores of the ocean and the Baltic Sea. 



It is, however, very rarely that we see companies composed of old 

 ones ; these seem to come more frequently by chance, and separately : 

 the yearlings of almost every species pass regularly by these parts of 

 the sea, and they are generally young individuals, or only one or two 



