COMMON AND BRUNNICH'S GUILLEMOTS. 



399 



It is not known that the forms recognized as Brunnich's Guillemot, Pallas's 

 Guillemot, or the Calit'ornian Guillemot ever possess either the white ring 

 or the white line behind the eye. The eggs of the Ringed Guillemot are 

 not distinguishable from those of the common form, and are subject to the 

 same variations. 



Brunnich's Guillemot only differs from the common bird in the shape of 

 the bill, and in having the base of the upper mandible pale horn-colour, a 

 peculiarity also found in Pallas' s Guillemot. It is a very rare straggler 

 to the British Islands during autumn and winter. It has been most 

 frequently observed in the Orkneys and extreme north of Scotland, but 

 there can be little doubt that it is often overlooked and confused with its 

 smaller-billed ally. 



