BLACK-HEADED GULL 



157 



nesting close to the sea. Although nests have been observed in low 

 trees, they are placed as a rule on the ground near water, and have in 

 some localities been found actually floating on the water itself, being in 

 such instances structures of great bulk. The nests may contain two, 

 three, or four eggs each ; but three appears to be the normal number, 

 and when there are four they are probably the product of two birds. 

 The eggs themselves, which range in length from just short of 

 2 inches to nearly 2^, vary much in colour, occasionally even 

 in the same clutch. Thus while the ground-colour may be greenish 

 grey, olive - buff, or 

 olive - brown, the 

 markings of various 

 shades of brown and 

 blackish are singu- 

 larly inconstant in 

 form and size, al- 

 though the under- 

 lying markings are 

 always pale violet. 

 Uniformly blue eggs 

 are not unknown ; 

 and there is a con- 

 siderable amount of 

 variability in regard 

 to the shape of the 

 eggs. The name of 

 laughing gull, it may 



be added, is derived from the hoarse, cackling cry of the species, which 

 when rapidly repeated has been likened to a rude laugh. 



Of the North American Bonaparte's gull {Larus pkiladeiphm, or 

 L. bo7iapartei), another small dark-headed species distinguished by its 

 black beak and leaden-black head, nine examples were recorded from 

 the British Islands up to the end of the nineteenth century. Of these 

 three were taken in Ireland and three in Cornwall, while one came from 

 Scotland. 



Of another allied species, the ^Mediterranean black-headed gull 

 {Larus melmiocepJialus), distinguished by the coal-black head and coral- 

 red beak of the adult, two examples were taken at Falmouth in 185 i, 

 a third was killed on the Thames in 1866, and a fourth near Yarmouth, 

 Norfolk, in 1887. 



This, however, does not complete the list of species of black-headed 



MOUNTED \U THE ROWLAND V.ARD STUDIOS 



BLACK-HEADED GULL (WLNTER) 



