290 Mr. Montagu's Observations. 



assumes more of the dusky or brown feathers than usual ; while 

 the middle coverts of the wings retain the mottled brown, and the 

 tail the dusky bar at the end. This, though we consider it as an 

 irregular change, may be admitted as an unusual variation in the 

 gradations commonly observed ; for scarce an instance is to be 

 found but what the brown scapulars and middle series of the 

 wing coverts are changed for those of gray, and the tail becomes 

 wholly white before the head is so much as covered with dusky 

 feathers, or the legs become more than reddish. 



The fourth change is that which has been generally known by 

 the Red-legged Gull. Lath. Syn. vi. p. 381. Lams cinerarius 

 Gmel. Syst, ii. p. 597. Larus ridibundus Ind. Orn. ii. p. 812. var. & 

 and in the Orn. Diction, is given under the title of Gull-red-legged 

 with a reference to Gull-black-headed. 



In this change, which brings it so near maturity, we find a very 

 material difference ; for not only the scapulars and coverts of the 

 wings are become gray, but the bar at the end of the tail is lost, and 

 that part assumes a pure white; the legs and bill also become of 

 a fine purplish red; these last, however, grow darker as the spring 

 advances, and the black increases on the head, a circumstance we 

 believe peculiar to the breeding season, when that colour spreads 

 over the whole of the head, taking in the throat; and in this, the 

 most perfect or adult state, it is the Black-headed Gull. Lath, 

 Si/n. vi. p. 380. Larus ridibundus Gmel. Syst. ii. p. 601. Ind. 

 Orn. ii. p. 811. 2. and the Gull-black-headed of the Ornithological 

 Dictionary. 



Having now traced the Black-headed Gull through its various 

 stages of plumage, after long experience and investigation, we 

 trust the numerous synonyms will, in future works on Ornitho- 

 lo"v, be concentred to one species, Larus ridibundus. 



THORACIC 



