34 THE BIRD WATCHER 
when, after some whik@l found and took up another 
baby, almost as big as the first, there was still less 
demonstration than in the case of the two fluffy ones 
—again excepting the parents. Perhaps the boiling 
point of communal fury that had been aroused by my 
first unlawful act was not to be again reached; but 
birds are certainly capricious in their actions, and 
there is no judging from one to the next. 
But, taking them at their best, why are these nor- 
thern terns so much fiercer and more vengeful than 
those which breed in the south? Of the disposition 
of the latter I] have had ample time to judge, and, 
though there was always anger when I walked over the 
great bank crowded with their nests, yet its manifesta- 
tions were of a more ordinary kind, nor, as I say, did I 
notice any very acute development of it when I lifted 
a young one from the ground. Sometimes I think 
these Shetlanders look slightly smaller than the English 
kind, and always they seem to me to be more waspish 
and irritable in their disposition. Are they, therefore, 
of a different species—the Arctic, instead of the com- 
mon tern, or vice versd? The two, indeed, are so 
much alike that only an ornithologist—as ornitholo- 
gists tell us—is capable of distinguishing them whilst 
the birds are alive and at liberty. However, as the 
sole mark of distinction appears to consist in a hardly 
appreciable difference in the length of the tarsus, it 
is easier to understand the difficulty than how the 
ornithological eye, even, unsupported by a measuring- 
tape, manages to surmount it. But when would any 
