BRITISH MARSH-TITMOUSE. I37 



white tips of the coverts show as a double bar on the wing. The 

 under parts are white shading through buff to rufous on 

 the flanks. The bill is black ; the legs lead-coloured and irides 

 dark brown. The young bird is duller, the black head having 

 no sheen, and the whites on nape and cheeks are tinged with 

 yellow. Length, 4*25 ins, Wing, 2*4 ins. Tarsus, '6 in. 



British Marsh-Titmouse. Pants palustris dressen 

 Stejn. ^ 



The black-headed tits might be taken as one Holarctic 

 species with numerous geographical forms distinguished by 

 slight colour or structural variation, and, in Britain, represented 

 by members of two groups, the Marsh-Tit, P. palustris^ and 

 the Willow-Tit, P. borealis. The Continental race oi palustris 

 which breeds in Germany, Holland, Belgium and western 

 France is greyer than the British form and has slightly longer 

 wings and tail ; it is not known to have reached Britain nor 

 has our bird been recognised abroad. From the Willow-Tit 

 our Marsh-Tit can be told by its blue-black head and squarer 

 tail. The study of slight racial differentiation may seem trivial, 

 but is of value when tracing the origin of species ; when 

 extremes are compared the value of intergrading forms is 

 appreciated. The British Marsh-Tit (Plate 54) is probably 

 absent from Scotland and Ireland, except where it has been 

 recently introduced, and is rare in parts of Cornwall and Wales ; 

 elsewhere it is well distributed but less common than the Great, 

 Coal and Blue. 



Marsh-Tit is a misleading rather than incorrect name, for 

 though the bird is found in damp and marshy places it is as 

 common in dry woods and hedgerows and even occurs in 

 gardens. The absence of the nape spot distinguishes it at 

 once from the Coal-Tit, the glossy blue-black from the duller 



