STEPPES OF ASIA AND AMERICA 69 
Isles. The bird differs from the bustard in that water 
is necessary to it, and it makes regular daily visits to 
particular drinking-places. 
Very characteristic of the Asiatic steppes are the 
birds belonging to the genus Podoces, sometimes called 
chough-thrushes, which are members of the crow 
alliance, though their exact position is doubtful. 
Though capable of flight, they only fly with reluctance, 
but run swiftly, feeding upon insects and seeds, and 
nesting in bushes or sometimes on the ground. They 
haunt the desert regions where bushes of saxaul and 
tamarisk grow, and do not seem to drink, while the more 
grassy regions of the steppes often swarm with the 
Siberian lark (Melanocorypha calandra). 
In the American prairies game birds are represented 
by the prairie-hen (T’ympanuchus americanus), a form 
related to the grouse; also by the sage-cock (Centro- 
cercus urophasianus, Fig. 10), which feeds upon ‘sage- 
brush’ (Artemisia tridentata) in the western states, just 
as Pallas’s sand-grouse feeds upon Agriophyllum in the 
Asiatic steppes ; and by the prairie-chicken (Pedioecetes 
phasianellus). All these can fly rapidly and powerfully, 
but only rise when hard pressed, preferring to run along 
the ground, or squat among the herbage, as means of 
escaping notice. 
In the steppes of both the Old and New Worlds such 
forms as curlews, plovers, snipe, ducks, geese, and so 
on, with many of the smaller singing-birds, are abun- 
dantly represented in the breeding-season, but do not 
show any very notable adaptations to steppe life. 
Reptiles in the steppes and adjacent deserts are not 
numerous in species, but the individuals are often very 
abundant. In that part of the desert of Gobi which is 
called Alashan, lizards belonging to the genera Phryno- 
