THE TREE-CREEPER. 
168 
the bark of trees, or under the mosses and lichens that 
invest their limbs. In these pursuits its actions are 
more like those of a mouse than of a bird, darting like 
a great moth from tree to tree, uttering a faint trilling 
sound as it fixes on their boles, running round them in 
a spiral direction, when with repeated wriggles having 
gained the summit, it darts to another, and commences 
again ; and so intent is it on the object of pursuit, and 
unsuspicious of harm, that I have seen it swept from 
the tree with a stick. Mr. Pennant thinks that it retires 
into milder regions upon the advance of winter; but 
many certainly remain with us. In the early part of 
the spring, when food is comparatively scarce in the 
woods, it will frequent the mossy trees in our orchards 
and gardens ; but after a very short examination of 
them, is away to its usual retirements, seeking no 
familiarity with us, notwithstanding the social epithet 
it has obtained. This little creature is observed in no 
great numbers ; yet its actions and manners seem to be 
such as would tend to its increase. The female lays 
eight or nine eggs ; it roosts securely in the holes of 
large trees; and from its manner of feeding, and the 
places it inhabits, it can scarcely be destroyed by birds 
of prey ; yet, from some counteracting cause, our little 
certhia, instead of increasing, apparently becomes a 
scarcer bird. The limits that are appointed to the in- 
crease of all the inferior orders of creation are very 
worthy of remark. There may be periods when a great 
augmentation of individual species takes place ; but this 
circumstance is local, or temporary, and future numbers 
do not result from it. Some motive for the increase, no 
doubt, existed ; but, the object being accomplished, it 
ceases, and apparent events, or imperceptible causes, 
reduce the profusion of the race, so that certain num- 
bers only continue. This little tree-creeper, though al- 
ways active, seems to possess most animation and rest- 
lessness in the autumnal months. 
The yellow wagtail (motacilla flava) is so regularly 
seen with us in his season, as to be quite a common 
bird, breeding in our fields ; yet generally observed as 
he is, he always invites our attention, by his graceful 
