932 THE CALIFORNIA MURRE. 
looks like an oological bouquet. These differences, moreover, are probably 
constant as between given birds. At least we found by experiment in 1907 
that if a handsomely marked egg were removed, another of the same type 
might be expected in its place from one to three weeks later. 
The peculiar shape of the egg, big at one end and little at the other, in- 
sures that the egg when disturbed shall roll in a small circle. In facet, in the 
fittest specimens the little end marks the center of a circle whose radius is the 
longer axis of the egg. This provides for maintenance on narrow ledges 
\ SLEEPY MURRI 
SHOWING WINTER PLUMAGE 
under ordinary circumstances; but a sudden flight of the Murres is bound to 
precipitate some of the eggs. 
Not only are bare rocks and ledges utilized, but eggs are deposited under 
projecting stones, in crannies, caves, or even old Puffin burrows. When the 
birds nest in sheltered situations one pays a fearful price for close acquaint- 
ance \ Murre rookery is not so bad where the purifying rains have access 
to it, but the stench of a protected cave is overpowering. Eggs are sometimes 
so encrusted with filth as to be immovable, and fledglings are born into 
conditions which would shame harpies 
