NORTHERN CACTUS WREN 221 



red-flowered mistletoe {Phoradendron caUfornicum) which in many cases 

 partially or wholly concealed them. One nest lay on a level branch covered by 

 an unsual horizontal growth of mistletoe and showed only as a darkened mass 

 inside, but most of them were in round ball-like masses of mistletoe, commonly 

 at the ends of branches in terminal mistletoe rosettes, frequently so dense that 

 it was impossible to obtain nest statistics or photographs. One of the nests with- 

 out mistletoe protection was built under an unbrella-like mass of foliage. 



* * * When not built inside a mass of mistletoe the nest was variously sup- 

 ported — by a crotch, by a horizontal branch and the trunk of the tree, or by an 

 angle of branches. 



A summary of the nests examined was appended, showing that 31 

 were in cholla cactus, at heights of 2% to 6 feet from the ground, while 

 of the 64 others, "38 were in catsclaw (29 in red mistletoe), 17 in zizy- 

 phus, 5 in mesquite (in red mistletoe) , 4 in shrubby hackberry ; and al- 

 together 34 in red mistletoe. The approximate height from the gromid 

 varied from 4 to 9 feet. * * * "While some of the cholla nests 

 examined were substantial and well protected, most of them were de- 

 cidedly inferior to the nests found in other bushes and trees. Being 

 lower and more exposed to wind and storm, especially in the case of 

 those on top of the lowest chollas, they had apparently been blown to 

 pieces, presenting a most dilapidated appearance." 



In New Mexico, says Mrs. Bailey (1928) , "the bayonet-pointed heads 

 of the tree yucca (T'wc<7«ra<:/^<3s«) are often chosen. * * * Two nests 

 seen were safely placed between the spears of adjoining yucca heads." 

 F. C. Willard (1923) mentions some unusual sites in Arizona: "One 

 pair built for several years in the hollow cornice of a schoolhouse. The 

 entrance was through a hole cut one winter by a visiting flicker. An- 

 other site was in an old woodj)ecker's nesting cavity which was twenty- 

 five feet up in a large sycamore, one of a line of these trees extending out 

 from the foothills of the Huachuca Mountains. A broken-out cavity 

 in a sahuaro cactus is also rather out of the ordinary for a Cactus Wren 

 to choose as a nesting site." 



In coastal southern California, the choice of acceptable nesting sites 

 is more restricted. On the gravelly river washes, such as that of 

 the San Gabriel River, Opuntia parryi^ the only "cholla" {CyUndro- 

 puntia) present, is rather small in stature, so that only the largest 

 specimens offer suitable situations. Most of the pricklypears {Platyo- 

 puntia) are procumbent in habit, but a large- jointed form {O. occi- 

 dentalis) furnishes a few nesting sites of the required minimum 

 height of 2 or 2i/^ feet. Large clumps of this latter species also occur 

 on some of the south- fronting hillsides. Thorny trees and shrubs are 

 absent, but nests are occasionally built in large bushes such as RhiLS 

 laurina and R. ovata^ or even in orange trees in a grove, at heights of 

 around 8 feet. One nest was placed on a four-by-four lookout under 

 the gable of a barn roof, another between palm leaves on the roof on a 

 pergola, and W. Leon Dawson (1923) mentions that "Mr. Frank S. 



