588 SYSTEMATIC SYNOPSIS. — GALLING — ALECTOBOPOBES. 
the same individuals ; and birds taken at different dates in the summer, in the same locality, 
may difi'er from one another more than specimens from different regions, representing several 
alleged varieties, are always found to do. The American bird, in 
fact, is scarcely distinguishable from the European L. mutus or alpinus. 
The Greenland bird has been called L. reinhardti by Brehm. That 
of the Aleutian Islands, L. mutus atkensis, Turner. The latter is 
said to have the bill and claws about 0.10 longer than usual. 
570. Li. leucvi'rus. (Gr. Xcvkos, leiicos, white ; ovpd, oura, tail. Fig. 405.) 
White-tailed Ptarmigan. Rocky Mountain Snow Grouse. 
9 , in winter : Entirely snow-white } bill black, rather slender, and 
general size and proportions nearly as in L. rupestris. $ 9 > hi sum- 
mer: Tail, most of the wing, and lower parts 
from the breast, remaining white ; rest of the 
plumage minutely marked with black, white, 
and tawny or grayish-brown, varying in pre- 
cise character almost with every specimen ; but 
there is no difficulty in recognizing this white- 
tailed species, of alpine distribution in West- 
ern N. A. from the Arctic regions to New 
Mexico (lat. 37°). In summer, inhabits the 
mountain ranges from timber-line to the high- 
est peaks, in winter ranging lower down. 
Eggs very different from the heavily-painted 
ones of L. albus, of dull creamy complexion, 
minutely dotted over the whole surface with 
burnt-sienna, few of the markings exceeding 
a pin's head in size, and not thick enough 
to obscure the ground-color ; shape purely 
ovoidal, greatest diameter near the middle ; size 1.70 X 1.14 ; number variable, about a dozen. 
53. Subfamily ODONTOPHORIN>E : American Partridges and Quails. 
Head completely feathered, and usually crested^ 
the crest frequently assuming a remarkable shape. 
Nasal foss* not filled with feathers, the nostrils 
covered with a naked scale. Tarsi and toes naked, 
the latter scarcely or not fringed, the former scu- 
tellate. Size smaller than in Tetraonina. 
Our Partridges may be distinguished, among 
American Gallince, by the foregoing characters, but 
not from those of the Old World ; and it is highly 
improbable that, as a group, they are separable from 
all the forms of the latter by any decided peculiari- 
ties. The principal supposed character, namely, a 
toothing of the under mandible, is very faintly 
indicated in some forms, and entirely wanting in 
others. Pending final issue, however, it is expe- 
dient to recognize the group, so strictly limited geographically, if not otherwise. Several 
beautiful and important genera occur within our limits, but these Partridges are most numerous 
in species in Central and South America. Odontophorus is the leading genus, with perhaps 
15 species; Eupsychortyx and Bendrortyx are other extra-limital forms; and in all, some 
Fig. 405. — White-tailed Ptarniigiiu ; upper, in sum- 
mer; lower, in winter. (From Hayden.) 
Fig. 406. — European Partridge. (From Dixon. 
