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 196 THE CONDOR Vor. Xll ting until the full complement of eggs is laid, but this does not appear to be the case with the Nutcracker. Perhaps a reason for this is the early nesting season, for at this time of year the temperature is often so low, both day and night, that there would seem to be danger that the eggs would freeze were they not constantly cov- ered. On the morning of March 23 I found the nest empty and deserted, before I was sure that the complete set had been laid. I suspect that a pine squirrel took the eggs, for these animals were not uncommon in the vicinity. The second Nut- cracker's nest was found on April 28, in a similar situation to the first but a few feet higher up. It contained two fully fledged young, 'which flew away as I climbed the tree. --=_ On June 3 we moved camp to Pipestone Basin, Jefferson County. This basit] is a large open grass area, about 5,700 feet in elevation and surrounded by moun- tains. Pipestone Creek winds thru the center, bordered by open grass marshes and fringes of willow bushes. Near the upper end of the basin the willows form dense impenetrable thickets. About the borders of the marsh, the higher and dryer parts of the basin are clothed in lux- Fig. 64. NEST AND EGGS OF V'IISON SNIPIS uriant bunch grass and sage- brush, and slope gently up to meet the scattered firs that mark the edge of the mountain forest. At this season of the year bird life was very abundant in the basin. About our camp on the edge of the forest, Robins, Moun- tain Bluebirds, Red-shafted Flickers, Ruby-crowned King- lets, Pink-sided Juncos, Western Tanagers and Hammond Fly- catchers were common. From farther up the mountain slopes came songs of the Olive-backt and Audubon Hermit Thrushes. In the willow thickets were Willow Thrushes, Mountain Song, Lincoln and Slate-colored Fox Sparrows, Warbling Vireos, Yellow-throats, and Lutescent and Pileolated Warblers. In the open grass of the basin were Vesper and Savannah Sparrows, Brewer Blackbirds and Western Medowlarks, while from a mass of boulders on the other side came the tinkling song of the Rock Wren. My first nest was a common one, that of a Magpie (Pica pica h,dsonia) placed in the top of a fir tree, a rather uncommon situation in this region, and containing four nearly grown young. On June 8 we experienced a late spring snowstorm, and when I climbed to this nest the next day, I found that it contained two dead birds and one live one. I have seen other cases where young Magpies have died in the nest apparently because of late spring snowstorms. Magpies in this region most commonly lay six or seven eggs. Only once have I seen a full set of as few as .four. On the other hand I have never seen a brood of young Magpies out of the nest that numbered more than three. These observations seem to show that there isa high mortality among young Magpies possibly due to late spring snowstorms. When climbing the tree to this nest, the parent birds became very much ex-