i 4 SPRING 



purely a question of what kind of twig comes handiest. 

 The clay cup of the nest is extremely solid and durable, and 

 lasts for many years, long after the wattle-work of the roof 

 and outer walls has decayed. 



Crows also fix their nests to the bough with a firm 

 foundation of mud ; and this firm mud and wattle architec- 

 ture is well devised against the gales of early spring. Rooks 

 differ from crows both in using no mud for the foundation, 

 and in lining the nest with leaves and grass instead of wool. 

 Rooks' nests are less strongly and comfortably built than 

 crows', and more often get blown down by the March gales ; 

 yet it is wonderful to see the bulky nest so often swinging 

 unharmed among the small branches at the top of a tall elm. 

 When massed on stronger boughs, the nests of an old 

 rookery accumulate in a dense floor on which one can safely 

 stand. The decaying sticks and grass-tufts make a sort of 

 leaf-mould, in which grass seeds and grains dropped by the 

 rooks shoot green in the moist spring weather. Among 

 these old deserted homes are interspersed the newer nests, 

 with sets of eggs or young. Again unlike crows and 

 magpies, which seldom use the same nursery in a second 

 season, rooks often patch up and reline their nests ; but 

 eventually the sticks grow too rotten to hold securely to the 

 branches, and the old nest is allowed to sink into a flat 

 platform, adorned with its springing herbs. The young birds 

 find these old nests useful perches when they are fledged 

 and flap abroad in May. 



Heronries are peopled as early in the year as rookeries, 

 and in mild seasons the full set of pale blue eggs is some- 

 times laid before the end of February. Unlike many other 

 birds, herons are most gregarious in the nesting season. 

 After they leave the heronries in late summer they are most 

 often seen about the marshes and stream-sides singly; we 



