COMMON AND BRUNNICH'S GUILLEMOTS. 389 



Colymbus minor (Tunst.), Gmel. Syst. Nat. i. p. 585 (1788). 



Uria troile (Linn.}, Lath. 2nd. Om. ii. p. 796 (1790). 



Una troile leucophtalruos, Faber, Prodr. Isl. Orn. p. 42 (1822, Ringed variety). 



Uria lacrimans, Valenc. Choris, Voy. pitt. autour du Monde, pi. 23 (1822, Ringed 



variety). 



Uria leucopsis, Brehm, Beitr. Vogelk. iii. p. 880 (1822, Ringed variety). 

 Uria minor (Gmel.}, Steph. Shaw's Gen. Zool. xii. pt. 2, p. 246 (1824). 

 Uria intermedia, Nilss. Skand. Faun. ii. p. 548 (1858). 



Catarractes troille (Linn.}, I Bryant, Proc. Bost. Soc. Nat. Hist. viii. pp. 136, 139 

 Catarractes ringvia (Lath.}, \ (1861). 



Alca lomvia (Scop.}, Schley. Mus. Pays-Bas, Urinatores, p. 16 (1867). 

 Lomvia troile (Linn.}, 



pp 



Lomvia ringvia (Lath.}, 



ALCA TROILE CALIFORNICA. 



CALIFOBNIAN GUILLEMOT. 



Catarractes calif ornicus, Bryant, Proc. Bost. Soc. Nat. Hist. 1861, p. 11 ; et aucto- 



nun plurimorum (Baird, Brewer, Sf Ridgway}, &c. 

 Lomvia californica (Bryant), Coues, Proc. Ac. Nat. Sci. Philad. 1802, p. 79. 

 Lomvia troile californica (Bryant), Ridyw. Proc. U. S. Nat. Mm. 1880, p. 212. 

 Uria troile californica (Bryant}, Baird, Brewer, $ Ridgway, Water-Birds N. Amer. 



ii. p. 483 (1884). 



There are two forms of the Common Guillemot, which some naturalists 

 regard as distinct species, others as varieties, whilst many look upon the 

 Ringed Guillemot as an accidental sport of frequent occurrence. So far 

 as is known, wherever one form occurs, both in the Atlantic and the 

 Pacific, the other is found with it, the proportion of Ringed Guillemots 

 varying in different localities from one in five to one in twelve of the 

 Common Guillemot. It is not known whether the young of the Ringed 

 Guillemot has always a ring ; but the two forms have frequently been seen 

 paired together, and the white line behind the eye is said to vary in length, 

 leading to the supposition that intermediate forms are found. It has been 

 regarded by some naturalists as a case of dimorphism ; but this term is 

 generally applied to cases where two females which differ from each other 

 have the same male. It seems to be well established that the difference 

 has nothing to do with age, sex, or season ; but the specific distinction 

 between the two forms must be left an open question until it can be ascer- 

 tained that the characters are hereditary. In the meantime it is better to 

 keep the nomenclature distinct, though we may treat the two forms as one 

 species, since no difference in their habits is known to exist. 



The Guillemot is a plain, not to say uninteresting, looking bird ; but 

 of all British sea-fowl, none are associated with so much that is attrac- 

 tive and romantic. The picturesqueness of its breeding-grounds, the 

 numbers in which the birds congregate together, the busy stirring scene 



