The eggs of this Wren obtained by Dr. Palmer in Arizona have a clear white ground, sparingly spotted with well-defined, distinct dottings of brownish-red. These are chiefly distributed around the larger end. They vary somewhat in size and shape, some being of a more rounded form, though all have one end more pointed than the other. The length is pretty uniform, .77 of an inch. The breadth varies from .60 to .66 of an inch. They are larger and more oblong than the eggs of any other Wren, except perhaps the _mexicanus_, and bear little resemblance to any other eggs of this family with which I am acquainted, except those of the Winter Wren, and the egg attributed to _T. americanus_. The nest is homogeneous in structure, composed entirely of thin strips of reddish-colored bark and fine roots, interspersed with a few small bits of wool. It is distorted by packing, so that measurements of it would be valueless; its dimensions in its pressed condition are: diameter, 5 inches; depth, 2 inches. The cavity is shallow and saucer-shaped. From Mr. Ridgway we learn that from the summit of the Sierra Nevada eastward, as far as the party explored, he found this Wren universally distributed. In the middle provinces of the Rocky Mountains it was the most abundant species of the family, but was not so abundant in the Wahsatch Mountains. The general resort of this species was among rocky or stony hill-slopes, though it was not confined to such localities. At Carson City he found it particularly partial to the rubbish of the decaying pine-logs. At Virginia City it was the only Wren seen frequenting the old buildings and abandoned mining-shafts, in its predilection for such places reminding him very much of the _Thryothorus ludovicianus_, which in its manners it very strongly resembles. Mr. Ridgway noticed a wonderful variety in the notes of this Wren. Its peculiarly guttural _turee_ was repeatedly heard, and its song in spring had a slight resemblance in modulation to that of the Carolina Wren, though altogether lacking the power and richness so characteristic of the superb song of that bird. Frequently its song was changed into a prolonged monotonous trill, similar to the tremulous spring-call of the _Junco hyemalis_. This species is not so wary as the _Catherpes mexicanus_. Upon suddenly starting up an individual of this kind, he would fly to the nearest boulder, turn with his breast towards the party, swing oddly from side to side, all the while ludicrously bowing and scolding the intruder with his peculiar sharp expressions of displeasure.