THE ROCK WREN. “417 
dozen of the likeliest. And when it comes to lining the approaches of the 
chosen cavity, what do you suppose they use? Why, rocks, of course; not 
large ones this time, but flakes and pebbles of basalt, which rattle pleasantly 
every time the bird goes in and out. These rock chips are sometimes an inch 
or more in diameter, 
and it is difficult to 
conceive how a bird 
with such a delicate 
beak can compass 
their removal. Here 
they are, however, to 
the quantity of half 
a pint or more, and 
they are just as much 
a necessity to every 
well-regulated — Sal- 
pinctean household, 
as marble steps are 
to Philadelphians. 
The nest itself is 
rather a bulky affair, 
composed of weed- 
stalks, dried grasses, 
and fine rootlets, 
with a scanty lining 
of hair or wool (all 
Fast-side birds are 
enthusiastic advc- 
cates of sheep-rais-: 
ing). “Two broods 
are raised in a sea- 
son, the first set of 
eggs appearing early 
fein the second "ter in Douglas County. Se i aa 
NESTING-SITE OF ROCK WREN IN BASALT CLIFF. 
about the middle of 
° . THE NEST OCCUPIES THE UPPER CRANNY BUT THE “FRONT WALK” Is 
June. It 1S possible COMPLETED BELOW. 
that even a third set 
may sometimes be laid still later in the season, but these late sets are more 
apt to be due to the breaking up of the first or second. The eggs vary from 
five to seven, and are pure white in color, sprinkled rather sparingly over 
the surface with dots of a faint brownish red, most heavily about the larger 
end” (Bowles). 
