1580 U.S. NATIONAL MUSEUM BULLETIN 23 7 pabt 3 



barbed-wire fence bordering the territories in which these nests were 

 located." 



Not only does the female gather the nesting material within the 

 territory but occasionally she helps to scrape out a shallow depression 

 for the nest when such excavation seems necessary (Mickey, 1943; 

 Silloway, 1902). "A new nest was constructed for each brood," 

 writes Mickey, "usually at some distance from the old one, either 

 within the previous boundaries of the territory or close enough to it 

 so that, in un crowded portions of the field, adjustments in the 

 boundaries could easily be made." 



Bailey and Niedrach (1938) found that "It is an easy matter to 

 locate nests * * * after the song perches have been discovered, for 

 the females are almost sure to be tucked away in the near vicinity, 

 and it is only a matter of walking about until they flush from under 

 foot." But, as they found, this is the beginning, not the end of the 

 problem. Nests are hard to locate, they learned. "Even when in 

 the open, cut by only a few blades of wiry grass, they are difficult to 

 see." To which Mr. Bent (1908) and DuBois (1937b) agree. In 

 DuBois' opinion, "Typical nests are not effectively hidden by grasses; 

 but * * * a nest may be effectively camouflaged by scant grass-clusters 

 slanting over the top of it, or by dry blades of grass hanging loosely 

 over it. It is surprising how few such blades are necessary to make 

 an effective camouflage." 



Parasitism of the nests by cowbirds does occur although apparently 

 only a few instances have been recorded. Currie (1890) in Minnesota 

 found a cowbird's egg in a nest from which he had removed four 

 McCown's eggs the previous day. And John Macoun (1909) in 

 Saskatchewan, in April 1894, discovered a cowbird egg in a nest of 

 four longspur eggs. 



Eggs. — The usual number of eggs per clutch is three or four, occa- 

 sionally five, though Sclater (1912) mentions six. Walter Raine 

 (1892) says that in the nests he discovered at Rush Lake, southwest 

 Saskatchewan, "the number of eggs to a clutch is usually five, some- 

 times only four. In my collection I have seven clutches of five eggs, 

 and four clutches of four." Farther west at Crane Lake Macoun 

 (1904) found two nests with four eggs each. Brown (Roberts, 1932) 

 reported 11 sets gathered in Minnesota between 1891 and 1899, of 

 which 6 sets numbered three eggs each and 5 held four eggs each. Of 

 52 nests DuBois (1935) studied in Montana between 1915 and 1918, 

 24 had sets of three eggs, 26 had sets of four eggs and 2 contained sets 

 of five eggs. In Oklahoma M. M. Nice (1931) found one nest with 

 five eggs and one with six eggs. 



Average size of eggs seems to vary from .80 by .65 inch, as re- 

 ported by G. B. Grinnell (1875) from North Dakota, to .81 by .57 



