1 86 The Alps in September. 



remarkable bird ; as large, said Anderegg, as a 

 fowl, using precisely the same comparison which 

 occurred to Aristotle two thousand years ago. 



We then descended rapidly into the Haslithal, 

 where I spent one whole day in noting such of its 

 feathered inhabitants as had not already deserted 

 it, or were likely to stay in it during the winter. 

 The most remarkable feature of this broad and 

 flat hollow in the hills, is the river Aar, which has 

 been artificially confined for several miles within 

 a strong stone embankment. On this particular 

 day the stonework on each side was literally alive 

 with Wagtails ; the left bank seemed almost ex- 

 clusively occupied by the gray species, and the 

 right bank by the white. All these were con- 

 tinually flying out over the swift glacier water, 

 hovering for a few moments as they sought for 

 flies, and then retiring to their station on the bank; 

 and this was going on for the length of a full mile 

 between the two bridges, so that the whole number 

 of Wagtails must have been enormous. I could 

 hardly avoid the conclusion that these birds had 

 collected in view of migration. The Gray Wag- 

 tail, Anderegg tells me, is never to be seen here 



