NORTHERN CACTUS WREN 219 



name herlandieri; these specimens were puzzling for a while, until 

 enough of the Mexican race could be obtained for comparison ; so it was 

 not until 1890 that this isolated race could be satisfactorily described 

 and named. He says that "this bird breeds near the ground, seldom 

 higher than 5 feet, in hollow trees, stubs, and even dead limbs lying on 

 the ground." He could not discover that it differed in any of its habits 

 from typical Carolina wrens elsewhere. He collected a number of 

 eggs, which were evidently similar to those of the northern bird. 



Eggs. — The eggs of this wren are indistinguishable from those of 

 other races of the species. The measurements of 40 eggs average 19.2 

 by 14.6 millimeters ; the eggs showing the four extremes measure 21.5 

 by 14.6, 20.5 by 16,2, 16.8 by 14.5, and 17.4 by 13.0 millimeters. 



HELEODYTES BRUNNEICAPILLUS COUESI (Sharpc) 



NORTHERN CACTUS WREN 



Plates 39-42 



HABITS 



Contributed by Robest S. Woods 



Best known through the abundance of its conspicuous flask-shaped 

 nests, the cactus wren well repays a close acquaintance with its own 

 interesting and unique personality. It is a bird that cannot easily 

 be confused with any other North American species, either in ap- 

 pearance or habits. 



The northern cactus wren is widely distributed through the Lower 

 Sonoran Zone along the Mexican border from Texas to the Pacific 

 and as far north as southern Utah and Nevada, but it is actually found 

 only in those comparatively limited regions where thorny shrubs and 

 trees or the more aborescent species of cactus offer nesting sites at 

 least 2 or 3 feet above ground and capable of supporting its bulky 

 structures. Vegetation of this type is frequently encountered on sunny 

 hillsides, on the mesas adjacent to mountain ranges, and along gravelly 

 watercourses. Though primarily a species of the lower country, Mrs. 

 Florence Merriam Bailey (1928) cites records of the cactus wren's 

 occurrence at altitudes of approximately 6,000 feet in New Mexico. 

 W. E. D. Scott (1888a) states, however, that in southern Arizona 

 it is "seldom found above 4,000 feet on the foothills of the several 

 mountain chains traversing the Territory." 



On the Pacific slope of southern California, suitable habitats are 

 much less plentiful than in the more arid regions to the eastward 

 and are steadily being reduced by cultivation and subdivision or by 

 mere growth of population with its attendant increase in vandalism. 

 Unlike many desert birds, the cactus wren accepts the encroachments 

 of civilization rather graciously, and occasionally it builds its nest 



