794 A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



arched and with only one distinct groove, though often indication 

 of a second. Nostril in adult very narrow slit in distal corner of 

 feathered portion of culmen and almost concealed by feathers, in 

 first winter wider and more exposed. 



Soft parts. — Bill black with a curved line white in summer 

 adult, greyer in winter adult, duller grey in second winter and 

 absent in first winter and summer ; legs and feet black ; iris dark 

 brown. 



Characters. — No subspecies. Pointed tail-feathers, deep bill and 

 white or whitish fines from culmen to eye distinguish it. 



Field -characters. — Essentially maritime, coming ashore only in 

 breeding-season and then restricted to cliffs, expert swimmers and 

 divers, short-winged, of robust build and with well marked colour 

 patterns, Auks in haunts, habits and appearance constitute a well- 

 marked group, whilst their pronounced specific differences make 

 identification easy. Razorbill differs from Southern Guillemot in 

 having black upper-parts, deep compressed bill marked by white 

 transverse line and, in breeding season, line from its base to eye, a 

 well-defined white wing-bar, and pointed tail which is elevated when 

 swimming. Call a grunting croak ; the young bird utters a mewing 

 cry. 



Breeding-habits. — Breeds in colonies associated frequently with 

 Guillemot on precipitous sea-cliffs, but lays its egg generally in 

 crevice or hole, instead of on open ledge like Guillemot. Makes no 

 nest. Egg. — One only, ovate rather than pyriform, surface rougher 

 and more granular than Guillemot's, and less variation in colour, 

 which ranges from light chocolate to white as a rule, but is occasion- 

 ally greenish, blotched, spotted, speckled or zoned with rich vandyke 

 brown ranging to black. Internal membrane shows greenish against 

 light. Average of 110 eggs, 74.91x47.34. Max.: 82.4x44.1 and 

 75.9 x 52.4. In. : 63.5 x 44.7 and 68.1 X 44 mm. Breeding -season. 

 — First eggs usually laid about May 9 or 10 (exceptionally late in 

 March !), and commonly after mid-May. Incubation. — By both 

 sexes. Period variously estimated at 26 to 35 days ; 30th day in 

 incubator. Single brooded. 



Pood. — Chiefly small fish, generally sand-eels (Ammodytes tobianus), 

 occasionally small smelts, herrings, sprats and Gasterosteus. 

 Florence also records Crustacea (Amphipoda). 



Distribution. — British Isles. — Resident. Breeds suitable cliffs 

 (mainland and isles) throughout (doubtfully Dover cliffs). Less 

 plentiful than Guillemot except in Ireland. Fairly generally 

 distributed in seas autumn and winter (rare Irish seas winter) and 

 frequently washed up on coasts, and occasionally storm-driven 

 inland. 



Distribution. — Abroad. — Islands and coasts of North Atlantic, 

 breeding as far south as Channel Islands and Brittany, and in 

 America to Fundy Bay and Gulf of St. Lawrence. In winter south 



