THE RED-THROATED DIVER. J ?9 



dropped it ; it afterwards swallowed two when in the seclusion of its basket. 



The adult male in summer has the bill (which appears to be slightly recurved, 

 owing to the nearly straight upper mandible and the long upward curve of the 

 lower) lead colour or blackish ; iris red ; forehead, face, sides of head, chin, upper 

 part of the throat and sides of upper neck slate-grey (ashy-grey in younger birds). 

 Top of the head, with centres of feathers, blackish-brown ; nape and hind neck 

 black-brown, with slight green reflections, marked with narrow white lines, caused 

 by white feather edgings ; as these feathers are not flat, but curved up at the 

 edges, the white lines are curiously raised. Back and sides of lower neck dark 

 brown, spotted with white. All the upper parts below this dark or blackish-brown, 

 with a slight green gloss ; in some cases some of the white spots of winter remain, 

 chiefly on the wing-coverts. Primaries blackish -brown, inner webs rather paler ; 

 tail blackish-brown. A large elongated triangular patch of reddish-chestnut extends 

 from a point on the throat nearly to the upper breast. Lowest part of the neck 

 below the chestnut white, in some cases marked with brown, probably a sign of 

 youth. Breast and belly white, with a few brown marks on the sides of the upper 

 part of the former ; sides of the body and flanks heavily marked with dark brown. 

 Under tail-coverts chiefly dark brown. An undated skin, examined by me, has 

 some of the primaries edged near the tips with yellowish-white ; this bird is in 

 worn summer dress, and shows some signs of immaturity. Length 24 or 25 

 inches; wing iroo to n'5- Larger as well as smaller measurements have been 

 stated. Weights of 3 Ibs., 4 Ibs. and 4-75 Ibs. are recorded. The female is rather 

 smaller. Tarsi and feet blackish. 



The adult in winter has the bill pale bluish-horn colour, darker on ridge of 

 culmen ; iris indian-red ; top and upper sides of the head, nape and back of the 

 neck grey, mottled finely with blackish and white ; the markings on the neck in 

 the form of narrow lines. Mantle, back, rump, tail- and wing-coverts dark grey, 

 marked with small white spots or short narrow lines. The white markings on 

 these parts are most conspicuous immediately after the moult, and gradually 

 diminish. Primaries and tail dusky grey, latter tipped with white. Chin, throat, 

 front and sides of the neck and face, extending to the lores and a narrow line to 

 the nostril, white. Under tail-coverts chiefly white ; a line of dusky feathers across 

 the lowest part of the belly. Inside of tarsus and the toes pale bluish-horn colour, 

 the outer side dusky. 



In young birds the feathers of the back and wing-coverts are edged with 

 white ; this edging being lost first at the tip of the feathers, the markings remain 

 as diagonal lines. The sides of the head and the throat are tinged with ash-grey. 

 Young in down brownish-black above, greyish-brown beneath (Seebohm). Au 



