496 ALCIDM 



white ; secondaries edged with white which forms a narrow 

 alar bar; primaries, greyish-black; tail (of 12 feathers), 

 similar in colour ; lower neck, breast, abdomen, and under 

 tail-coverts, white ; over the eye is a small white patch. 



Adult female nuptial. Similar to the male plumage. 



Adult winter, male and female. Chin, lower portions 

 of the cheeks, throat, sides and front of neck, 1 white ; other- 

 wise similar to the nuptial plumage. 



Immature, male and female. Resembles the adult 

 winter-plumage, except that the feathers of the upper parts 

 are not glossy. 



BEAK. Blackish ; short and strong. 



FEET. Brownish-green, with darker webs. 



IRIDES. Light brown. 



AVERAGE MEASUREMENTS. 



TOTAL LENGTH 8 - 5 in. 



WING 4-6 



BEAK 0*65 ,, 



TARSO-METATAESUS 0'9 ,, 



EGG 1-9 x 1-25 in. 



1 In spring and autumn these regions are mottled with black and 

 white : I have several times picked up Common Guillemots showing this 

 transitional stage of plumage. 



