222 THE SCOTTISH NATURALIST 



those of the primaries) are edged more or less broadly with 

 " light drab " {vide Ridgway), these edgings on the coverts 

 forming a broken band across the wing. Some of the feathers 

 of the upper and under tail-coverts are also edged with "light 

 drab." A slight tinge of this same colour pervades the whole 

 of the plumage of the under surface below the throat. The 

 dusky patch of hair-like feathers in front of the eye (which is 

 found in both the adults and young of the pale form) are also 

 present. Her Grace describes the tubular nostrils at the 

 time of capture as being dark slate colour, thus differing 

 from those of the pale bird, in which they are light bluish 

 gray. The rest of the bill from the description seems to 

 closely resemble that of the pale form. The length of the 

 bill taken in a straight line from the forehead to the tip is 

 1-47 ins. (37 mm.); a similar measurement taken from a 

 typical male, also from St Kilda, gives the bill as 1-6 ins. 

 (41 mm.). The outer sides of the tarsus and the toes and 

 their webs are the same colour as the general tint of the 

 plumage : the inner sides somewhat paler. The iris was dark 

 brown. The wing measurements are 12-5 ins. (317 mm.), or 

 rather less than those quoted by Saunders {Manual of 

 British Birds) and by Salvin (B. M. Catalogue of Birds, vol. 

 xxv.) for the pale form ; their measurements being respec- 

 tively 13-25 ins. (337 mm.) and 13-2 ins. (335-2 mm.). 



The coloration of the dark form has been very differently 

 described by some of our leading British ornithologists. 

 Thus Seebohm alludes to it as being a " brown bird " ; 

 Yarrell (fourth edition) as " brown " ; and other authorities 

 described it simply as " dark slaty gray " ; while others again 

 have erroneously considered it as the immature stage of the 

 common bird. Koenig, in his beautiful work Avifauna 

 Spitzbergensis, affords us some valuable information regard- 

 ing this bird, based upon his own personal experience. He 

 describes it as being slate-coloured, with the under side 

 somewhat lighter gray; and furnishes the interesting infor- 

 mation that the chicks are uniform smoky-gray. The bill 

 and feet are in general darker. The colour of the beak of 

 adult individuals, says the same author, is really variable. 

 Mostly only the tip is beautifully yellow coloured, but 



