HERRING GULL. 555 



toward the end, ten or eleven-twelfths high at the angle, 

 Avhich is very prominent, the lower mandible with two 

 oblique ridges at the base ; tarsus two inches and eight- 

 twelfths long ; wings surpassing the tail by two inches. 



Adult in winter Avith the bill yellow, the lower mandible 

 with an orange-red patch toward the end ; the margins of the 

 eyelids yellow ; the feet flesh-coloured ; the back and wings 

 light bluish-grey ; the quills largely tipped with white, the 

 outer six in part black, two of them with a large w^hite spot 

 toward the end ; the head and hind neck Avhite, with light 

 brown streaks ; all the other parts pure white. 



In summer, the bill pure yellow, the patch on the lowri- 

 mandible bright orange, inclining to carmine, margins of 

 eyelids yellow ; the head and neck pure white, the other 

 parts as in winter. 



The first individual approaches in size to the Black-backed 

 Gull, and has the bill as large as in many individuals of that 

 species. The sides of the lower mandible have two oblique 

 ridges at the base, and its angle is very prominent, leaving 

 the outline on either side considerably concave. The nostrils 

 are linear-oblong, five-twelfths long. On the tarsus are 

 twenty-four scutella, on the hind toe two, the second toe 

 twenty-five, on the third thirty-six, on the fourth thirty-eight. 

 The wings and tail are in all respects as in Larus argentatus. 

 The first quill is white for two inches at the end, the second 

 white at the tip, and with a white spot near the end, the rest 

 tipped with white ; five of the primaries more or less black, 

 the sixth with a faint dusky mark. 



Length to end of tail 26 inches ; wing from flexure 18f ; 

 tail 7f ; bill along the ridge 2\^ ; along the edge of lower 

 mandible 3^; tarsus 2-^; first toe -j^^-, its claw -^ ; second 

 toe 11^, its claw -^ ; third toe 2jV, its claw -^ ; fourth toe 

 2^, its claw -^. 



The American specimen, although probably not more 

 than three years of age, two of the tail-feathers having a 

 dusky spot upon them, measures as follows : — 



Length to end of tail 27 j inches ; wing from flexure 18;^ ; 

 tail 71; bill along the ridge 2^, along tlie edge of lower 

 mandible 3, its height at the knob \^ ; tarsus 2y^^ ; hind toe 



