270 ANIMAL LIFE 
Fia. 164.—Nest of the Californian bush-tit (Psaltriparus minimus). Photograph by 
G. O, SNyDER, Stanford University, California. 
leries. The prairie-dogs make burrows in groups, forming 
large villages. 
The devotion to their young displayed by birds and 
mammals is familiar to us. The parents will often risk or 
