358 A SPRING AND SUMMER IN LAPLAND. 



this was more from wantonness than anything else. 

 I could scarcely distinguish the male from the 

 female by the plumage. In one example the long 

 middle tail feathers measured 13 inches, and ex- 

 tended 9 inches beyond the rest. Much confusion 

 has existed respecting the different members of 

 this group, and I believe it is due to the assiduity 

 of Bonaparte that much of this mystery is cleared 

 up, and that this skua is identified as a distinct 

 species. Perhaps no class of birds are subject to 

 so many changes in plumage, owing to age, and 

 different shades even at the same season of the 

 year, as the skuas ; and I cannot help here quoting 

 Wilson's very excellent remarks on this subject : 

 " The changes of plumage to which birds of this 

 genus are subject have tended not a little to con- 

 found the naturalist; and a considerable collision 

 of opinion, arising from an imperfect acquaintance 

 with the living subject, has been the result. To 

 investigate thoroughly their history it is obviously 

 necessary that the ornithologist should frequently 

 explore their natural haunts ; and to determine the 

 species of occasional or periodical visitors, an 

 -accurate comparative examination of many speci- 

 mens, alive or recently killed, is indispensable. Less 

 confusion would arise among authors if they would 

 occasionally abandon their accustomed walks, their 

 studies, and their museums, and seek correct Icnoiv- 



