192 • BIRDS OF ILLINOIS. 



posterior border of the arm-wing, a sma'l spot on each side of the back (nearly con- 

 cealed by the closed wing), and a larger one on each side of the rump grayish 

 white. Lower half of the head (from about on a line with the eye) brownish buff, paler 

 on the chin and throat; chest light dingy brownish; remaining lower parts dingy white, 

 the sides brown, like the upper parts. 



Total length, about 17.5d-19.00 inches; extent, 24.00-26.00; wing, 7.50-7.90 ; culmen, 1.50; 

 tarsus, 1.25-1.30; middle toe, 1.90-1.95. , 



The Hooded Merganser is a common summer resident in Illi- 

 nois, inhabiting wooded swamps and the dense timber along 

 streams, where it may be seen perching high in the lofty trees, 

 in knot-holes and other cavities of which it makes its nest. 



