16 The Ruffed Grouse 



position, as flying or walking, or fitting one part of the body into 

 another, as in roosting, and probably economy of weight. 



The Brood Spot: The female bird plucks the feathers from her 

 abdominal region during incubation in order to make proper body 

 contact with tlie large clutch of eggs. This bared area is called the 

 brood spot. Normally all of the feathers on this spot are plucked 

 except the filoplumes. Most of the abdominal region is plucked, as 

 well as adjacent portions of the sternal and axillar regions and the 

 femoral tract. 



The Numbers of Feathers on a bird may vary considerably. Some 

 indication of the number of feathers (teleoptiles and semiplumes) 

 in the various tracts may be gained from the figures of Trainer ob- 

 tained by plucking a female weighing five hundred thirty-nine and 

 seven-tenths grams, collected April 27, 1937. He points out that the 

 distinction between certain tracts is indefinite owing to the indefi- 

 niteness of some of the tract boimdaries. 



Total 4342 



Range. The ruffed grouse in its six subspecies is found over most of 

 the wooded areas of the United States and Canada. B. u. umbellus 

 ranges from the Appalachian Mountains in northern Georgia, 

 northern Alabama, and the Garolinas, through western Virginia and 

 Maryland, Tennessee and Kentucky, southern Ohio, Pennsylvania 

 and northern New Jersey, and northward approximately to a lati- 

 tudinal line through the center of Minnesota, Wisconsin, Michigan, 

 New York and northern Massachusetts. Here it blends into B. u. 



