THE SCOTTISH PTARMIGAN. 867 



much as in Red Grouse but usually clearer and more contrasted ; 

 under-parts paler than in Red Grouse especially on sides of head, 

 chin and throat ; toes covered with down. Down is replaced by 

 feathers of juvenile plumage. 



Juvenile . Male and female. — Upper -parts much like adult male 

 summer but more barred yellow and bars rather finer ; throat and 

 breast and flanks yellow-buff with rather narrow black-brown bars, 

 feathers with small white tips ; centre of breast, belly and under 

 tail-coverts buflish or dull white, more or less marked dusky ; all 

 tail-feathers much as upper-parts ; primaries brown mottled pale 

 buff on outer and edge of inner webs ; secondaries brown edged, 

 barred and mottled pale buff especially on outer webs, inner 

 secondaries more like upper -parts ; wing-coverts much like upper- 

 parts but more closely barred yellow-buff and with rather con- 

 spicuous small white wedge-shaped tips. 



First autumn. — Like adult autumn but rather more buflish on 

 upper-parts and always a considerable number of juvenile body- 

 feathers retained as well as some upper tail-coverts and inner 

 secondaries and greater coverts ; primaries in male as well as 

 female usually with thicker black shaft-lines than adult and often 

 speckled ; outer webs of some secondaries and greater coverts often 

 with patches of grey-brown ; outer primary-coverts often speckled 

 black-brown ; upper tail-coverts often with black-brown bases. 

 The juvenile plumage is moulted July-Sept, as in Capercaillie (see 

 p. 853, footnote) ; 1st and 2nd primaries are white and like the 

 first autumn primaries. First winter and first summer. — Like adults 

 and usually impossible to distinguish with certainty when com- 

 pletely moulted, but sometimes black speckling on primaries or 

 outer primary -co verts distinguishes them. N.B. — In course of 

 autumn moult there is great mixture of plumage, winter and 

 autumn feathers both growing before juvenile are all shed. 



Measurements and structure. — $ wing 190-200 mm. (1st autumn 

 182-195), tail 96-112, tarsus 29-36, bill from nasal groove 10-12 

 (17 measured). $ wing 178-195, tail 90-102. Primaries : 3rd 

 longest, 4th as long or 1-3 mm. shorter, 1st 38-48 shorter, 2nd 4-10 

 shorter, 5th 4-8 shorter. Rest of structure as in Red Grouse. 



Soft parts. — Bill black ; claws dark horn-colour ; iris brown ; 

 bare skin over eye red. 



Characters and allied forms. — Male and female L. m. millaisi 

 are paler and purer grey in autumn plumage than other forms and 

 female in summer is of rather richer golden-buff and has usually 

 narrower black bars. L. m. mutus (N. Europe) is rather larger and 

 has in summer male upper -parts darker and more finely barred and 

 vermiculated buff than in L. m. millaisi and many winter feathers 

 are retained, in autumn both sexes considerably buffer than L. m. 

 millaisi, in summer female upper-parts have more black and tips of 

 feathers are much vermiculated grey-white, black bars on under- 

 parts wide and tips of feathers white ; L. m. islandorum (Iceland) 



