Family LARIDAE. 



Larus argentatus Brunnich — Herring-Gull. 



(Plates 160—163, fig. a-h). 

 (Snouckaert: Avifauna Neerlandica, p. Ill, No. 262). 



Colour of surface of shell: 

 Colour of spots: 



Average dimensions: 

 Average weight of shell: 

 Texture of shell : 



Shape : 



Nest and Its site: 



Number of eggs: 

 Breeding season: 

 Duration of incubation: 



olive brown, olive yellow, olive green, or 

 olive grey, in various shades. 



olive yellow; from yellowish brown to 

 blackish brown; underlying spots show 

 through grey. 



71 >( 48 millimetres. 



6.2 grams. 



coarse-grained (the composing particles of 

 lime are very clearly distinguishable with 

 the aided eye. 



rather slender on the whole, but varies con- 

 siderably. 



a hollow in dune sand, mostly under the 

 shelter of sand-elymus plants and usually 

 with a lining composed of vegetable 

 material. (Breeds in colonies). 



generally 3. 



May, June. 



about 4 weeks. 



