438 Field Museum of Natural History — Zoology, Vol. IX. 



grouse supposed to be of this form appear to be only intermediates, 

 and typical umbellus occurs in the most northern counties." (p. 56.) 

 I have never seen a typical specimen of togata from Wisconsin, all 

 specimens examined being nearer to umbellus than to the northern 

 form. 



Genus LAGOPUS Brisson. 



143. Lagopus lagopus (Linn.). 

 Willow Ptarmigan. 



Distr.: British Provinces to Arctic regions; accidental in northern 

 New England and probably in other parts of the northern boundary 

 of the United States. 



Winter plumage, male and female: General plumage, pure white; 

 primaries, white, the shafts, blackish; most of the tail feathers, black, 

 tipped with white; feet, entirely feathered. 



In summer both sexes assume a barred and mottled plumage of 

 rufous brown, black, and buffy white. 



Length, 15 to 17.25; wing, 7.10 to 7.60; bill (nostril), .40. 



The Willow Ptarmigan must be considered a rare bird in extreme 

 northern Wisconsin in winter and it may have occurred in Illinois 

 during the past century, as Robert Kennicott states:* "Sometimes 

 found in the timber along Lake Michigan." Dr. R. P. Hoy procured 



♦Catalogue of the Animals observed in Cook Co., Illinois. Trans. 111. State Agricultural Soc, 

 Vol. I, i8s3, p. 586. 



