72 EUROPEAN MARSH-TITS. 



xxin, 1877, pp. 108-110), asserts that " as a rule P. borealis has a some- 

 what slenderer bill" than P. palmtris, ami from his tables of measure- 

 ments {torn, cit., p. 110) it is plain that in Norway the two forms are 

 of essentially the same size, P. palmtris being, if anything-, the larger 

 of the two. ' Nilsson, too (Skand. Fauna, Fogl., 3ed., I, p. 419), insists 

 that both forms are of the same size, and he adds that the shape of 

 the bill is also the same. If we now eompare the measurements which 

 I have taken myself (see tables below), it will be seen that they fully 

 bear out the various statements of the gentlemen quoted above. It is 

 I hen plain that the Scandinavian so-called P. borealis differs from the 

 one of the Alps by being smaller, with a much slenderer bill. The 

 latter form is Parus montanus (Baldenstein, 1S29)* in which name at 

 present I am obliged to include Victor Fatio's P. alpestris and P. borealis 

 {nee Selys), as I have no means of verifying their status, though 1 

 believe them to be separable ; nor do I know to which of the two forms 

 Baldenstein's name montanus and Bailly's alpestris strictly belong. 



But it is not only in size that the southern P. montanus differs from 

 its northern representative, for the hood is not black at all in the former, 

 being, as it is, of a dark sepia slightly mixed with reddish ; in fact, my 

 French specimensofP. montanus are qui^e as brown-headed as P. lugubris. 

 This difference in the coloration of the hood of the southern and north- 

 ern so-called P. borealis is also indirectly indicated in the comparisons j 

 instituted between these forms and P.palustris by the various authors. 

 Thus Fatio (loc. cit.) strongly contrasts the " deep lustrous. black with 

 blue reflections" of the latter, against the " blackish brown with red- 

 dish brown reflections" of the former {alpestris : "dark blackish brown, 

 with reddish brown reflections;" borealis: "blackish brown, a little 

 more pronounced than in P. alpestris, and with reflections even still j 

 more brown"). Collett and Nilsson {II. ce.), on the other hand, make 

 no distinctions as to color, simply saying that the hood in P. palustris 

 is more glossy. 



The shape of the tail is the same in P. montanus and P. borealis, and 

 on the whole they are nearer related to each other than is either of them 

 to P.palustris. They are only subspecies of the same species, but 

 whether they should bo designated by triuomiuals is quite a differed 

 question, and depends solely upon whether they are " known now to in- 

 tergrade" (A. O. U. Code, can. xi). £o far as I can find out they are not 

 known to intergrade; I consequently retain the binominal appellation! 



So far we have gained the following results : In Northern Europe the 

 true P. borealis occurs; in Central Europe the large and more brown- 

 headed P. montanus; their habitats are widely separated and isolated. 

 On the other hand, P.palustris occurs all over Europe (except in Groat 

 Britain, where it is represented by P. palmtris dresseri), breeding even 

 in the same localities in which P. borealis and P. montanus hreed. This! 



- Parus cinereus montanus Baldensteix, Neue Alpiua, II, ISiJ ([>. 21) iu-c Parui 

 montanus Gambel, Proc. Pbila. Acad., I, fS4:5, (p. 25 l J), qui Parus gambeli Ridgw. 



