SECOND WEEK IN JUNE 133 
and olive. These birds are very elegant in 
their movements on the ground. They may 
be found chiefly (but not exclusively) along- 
side streams or waters. They vun along the 
ground (never hop) and stop suddenly, wag- 
ging their tails all the while, and the louping 
flight is very graceful. (It is difficult to 
understand why these birds wag their tails.! 
Why, we might ask, has the great grebe the 
peculiar ruff, and there are many similar 
questions which occur to us if we think 
about them. Trying to find answers to these 
questions is part of the interesting study 
of natural history.) Some distinguishing 
features of the three wagtatls beside plumage, 
are: Yellow Wagtail: note, ‘ tweet,’ or ‘ tweet 
tweet.’ Does not generally go near houses. 
Often seen with cattle catching insects ; 
(2) Pied Wagtail : black and white plumage 
distinctive. More common than the yellow. 
Often seen near houses, on lawns, and amongst 
1 The constant wagging of the tail is probably to give 
them an impetus to move forward or fly up at any instant 
to catch a quick-flying insect. They run rapidly. 
