HYPOTHETICAL LIST. 755 
except by the expert. In all essential respects the Loggerhead has the 
habits and characteristics of the Migrant Shrike and the White-rump. 
TECHNICAL DESCRIPTION. 
Bill strongly hooked, wing less than 4 inches, tail averaging longer than wing, third 
and fourth primaries about equal, the fourth usually a little the longest. 
Adult (sexes essentially alike): Upper parts slate-gray to ash-gray, very little if at all 
paler on the rump and upper tail-coverts; nasal bristles, lores, and broad stripe around and 
behind the eye, clear black, the black continuous across the front of forehead; a faint 
white or grayish line between this black area and the gray of the top of head; under parts 
nearly pure white, sometimes faintly shaded with grayish on sides of breast and body or 
(in immature birds) slightly tinged with reddish; wings black, with a conspicuous white 
patch near the middle of the primaries, and most of the secondaries and tertiaries tipped 
with white; scapulars mostly pure white; central tail-feathers black, outer tail-feathers 
pure white or with a small black area near base, other tail feathers black broadly tipped 
with white; bill and feet entirely black; iris brown. Young: Similar to adults, but all the 
gray and white areas strongly washed with brownish; back and under parts with numerous 
wavy cross-lines of brown or dusky; greater wing-coverts tipped with rusty or buffy. 
Length 8.50 to 9.50 inches; wing of male 3.75 to 3.90, of female 3.66 to 3.78; tail of male 
3.89 to 4.15, of female 3.87 to 3.97; culmen about .59 (Wm. Palmer). 
White-rumped Shrike. Lanius ludovicianus excubitorides Swains. (622a) 
Separable from the Loggerhead and Migrant Shrike only by the expert, 
and with difficulty; often not separable at all. The Migrant Shrike is 
said to have “darker, duller plumage, especially beneath, to be stouter and 
longer, and to have larger bill, tarsi and feet.” (Palmer, Auk, XV, p. 251). 
It seems doubtful whether the true White-rumped Shrike, as distinct 
from the Migrant Shrike, ever occurs in Michigan. Tor the present at 
least we may relegate this species to the doubtful list. 
Its natural habitat is from the eastern border of the Plains to the Pacific, 
and from Manitoba and the Plains of the Saskatchewan south over the 
tablelands of Mexico. 
Parula Warbler. Compsothlypis americana americana (Linn.). (648) 
The typical form of the Parula or Blue Yellow-backed Warbler does 
not seem to be found in Michigan, being replaced by the northern form, 
C. americana usnee Specimens intermediate between the two forms 
occur in northern Indiana according to Butler (Birds of Indiana, 1897, 
p. 1040), and possibly some of these occur in southern Michigan, but all 
the specimens we have seen appear to belong to the northern subspecies. 
Yellow-throated Warbler. Dendroica dominica dominica (Linn.). (663) 
Very similar to the Sycamore Warbler (No. 280) which has been mistaken 
for it several times. The latter is readily discriminated with specimen 
in hand, since the stripe over the eye is almost or quite pure white, while 
it is distinctly yellow anteriorly in the Yellow-throated Warbler. The 
latter is a bird of the Southern Atlantic States, and there is no authentic 
record of its occurrence in Michigan. 
Brown-headed Nuthatch. Sitta pusilla Lath. (729) 
Smaller than the Red-bellied Nuthatch, with the top and back of head 
grayish-brown; no white over the eye, but a whitish patch on the nape. 
