136 Allen's naturai;ist's library. 



lie up in the line of the Harrier's flight to their roosting- 

 places ; for they always take the same course, and come, even- 

 ing after evening, within five minutes of the same time. Upon 

 one occasion, a friend and myself killed eleven, and during 

 that visit accounted for over twenty. We also, on every pos- 

 sible opportunity, destroyed the nest and shot the old ones ; 

 but it was the labour of Sisyphus, for others immediately ap- 

 peared. However, there was a visvble diminution of their 

 numbers about Casas Viejas. We never found rats in their 

 nests or crops, and believe that they have not the courage 

 to kill them : small snakes, frogs, wounded birds, eggs, and 

 nestlings form the main part of their prey." 



Nest. — The Marsh-Harrier is, in many places, gregarious 

 during the breeding-season and many nests are found in the 

 same vicinity ; at least this is the case in Southern Spain 

 and Marocco. The nest is made of dead sedge and reeds 

 with a few small branches, these being added to from time 

 to time. It is occasionally found in a tree, but is generally 

 placed in a reed-bed, sometimes on the ground and among 

 low brambles, always near water, but sometimes far from any 

 marshes. A disused nest of a Coot or Water-Hen is often 

 adopted. 



Eggs. — From three to six in number ; pale bluish white, very 

 rarely with any pale brown markings. When fresh blown, and 

 held up to the light they show a bluish tinge. Axis, i*8-2'i ; 

 diam., 1-55. 



THE GOS-IIAWKS. GENUS ASTUR. 



Astur, Lacep. Mem. de ITnst. Paris, iii. p. 505 (1801). 



Type, A. pahiinharws (L.). 



Although belonging to the long-legged Hawks, the Gos- 

 Hawks are much more stoutly built than the Harriers, and 

 have no facial ruff like the last-named birds. The hinder 

 aspect of the tarsus, also, is transversely scaled, and not arti- 

 culate or covered with a network of small scales as in the 

 Harriers. They comprise birds of all sizes, just like the 

 Sparrow-Hawks, many of the latter exceeding the smaller 

 Gos-Hawks in size. There is. however, one character by 



