Family FALCONIDAE. 



Circus pygargus (L.) — Montagu's Harrier. 



(Plate 101, fig. a-b). 

 (Snouckaert: Avifauna Neerlandica, p. 64, No. 152). 



Colour of surface of shell : 



Colour of spots : 

 Average dimensions: 

 Average weight of shell: 

 Texture of shell: 

 Shape : 

 Nest: 



Site of nest: 



Number of eggs : 

 Breeding season : 

 Duration of incubation: 



white, with a more or less bluish, sea-green 

 tinge; when light shines through the egg- 

 shell it shows through green. 



light havana-brown. 



40.6 >; 32.4 millimetres. 



2 grams. 



fine-grained. 



short-oval. 



consists of vegetable materials, sometimes 

 lined with hair and wool. 



In July 1899 a nest was found near Steen- 

 wijkerwolde which had a couple of side- 

 nests in each of which there was a young 

 bird. 1) 



on the ground. 



in corn-fields, tall grass, shrubs, etc.; by 



preference more in dry regions (on heaths 



and in the dunes). 



4 — 5, sometimes 6. 

 May— June, 

 about 3 v.'eeks. 



') Statement by Dr. C. Kerbert in the „Ornithologisch Jaaroverzicht" of Dr. 

 R. Baron Snouckaert van Schauburo, In: „De Levende Natuur", 5th annual 

 series, page 98. 



