109 
inferences, through a paucity of specimens ; not excepting even the 
l)iiinstaking and most accurate ^Magillivray, 
Of late, however, a new light has dawned upon us which seems 
likely to clear up many former doubts and difliculties. I 
allude to the now prevalent belief that each of our British species 
of Skua is subject, inore or less, to a melanistic variation of 
colouring. Hitherto, such dark birds have been regarded by many 
Ornithologists as representing merely some stage of immaturity, 
but a more careful examination and comparison of specimens has 
shown that, in other respects than more colour, many of these birds 
show indications of maturity, as surely as the light-breasted forms. 
iMr. Jlresser has drawn attention to this subject in his ‘ Birds of 
lairope,’ as in his observations on the i)lumagc of the Oreat 8kua 
(S/ercomrinn eatarrhactes), having ligured a most interesting 
melanism * of this species from the collection of ;Mr. J. 11. Gurney, 
jun., killed, in October, off Yarmouth, he remarks Like all 
the Skuas the pi’csent species has a dark, almost uniform sooty 
brown stage of plumage j l>ut whether this is a variety or melanism, 
or whether the dress of the very old bird, it is impossible to say. 
I lean, however, to the opinion that it is a sort of melanism 
irrespective of ago or sex, such as one sees in many of the true 
birds of prey.” 
It remains, however, for the specialist to deal with such intricate 
questions as those, and hapj)ily, when most needed, Mr. Howard 
Saunders, who has devoted infinite pains of late to the life history 
of Gulls, Terns, supplies us from his yet unpublished store of 
facts with such information, as acts in the same practical form as a 
housemaid’s broom in the demolition of cobwebs. In a com- 
munication to the ‘Field’ (January 17th, 1880) ou the migmtion 
of Skuas, he particularly remarks the occurrence, this last autumn 
on our east coast, of the black form of the Pomatorhine Skua, two, 
evidently adult specimens, recorded by ;Mr. T. A. Xelson, of 
Piedcar, and one which he saw in Mr. E. T. Booth’s collection at 
Brighton, which I believe I am correct in saying Avas shot by Mr. 
* Mr. II. Saunders, in a paper “On the Stercorariiiue, or Skua Gulls” in 
tlie ‘Proceedings of the Zoological Society’ for 187(3 (p. 320), also alludes 
to this most interesting specimen, which, from a careful examination of the 
plumage, lie considers, undoubtedly, to be a bird of the year. 
