The following is a comparative view of the measurements of several American and European birds.
| American. | European. | |||||||||||
| M. | M. | F. | M. | M. | F. | |||||||
| Length to end of tail, | 3 | 7/8 | 3 | 11/12 | 3 | 5/8 | 4 | 4 | 1/4 | 3 | 6/8 | |
| ................................wings, | 3 | 1/8 | — | 3 | 1/8 | 3 | 1/4 | — | 3 | 1/8 | ||
| ................................claws, | 4 | 3/8 | — | 4 | 2/8 | 4 | 1/2 | — | 4 | 1/4 | ||
| Extent of wings, | 6 | 1 1/2/8 | — | 5 | 3/8 | 5 | 7/8 | 6 | 1/2 | 5 | 3/4 | |
| Wing from flexure, | 1 | 7/8 | 1 | 11/12 | 1 | 7/8 | 1 | 7/8 | 1 | 11/12 | 1 | 7/8 |
| Tail, | 1 | 5/8 | 1 | 3/12 | 1 | 4/12 | 1 | 5 1/2/12 | 1 | 1/2 | 1 | 4/12 |
| Bill, | 5/12 | 5/12 | 4 3/4/12 | 5/12 | 5 1/2/12 | 5/12 | ||||||
| Tarsus, | 8/12 | 8 1/2/12 | 8/12 | 8/12 | 8/12 | 8/12 | ||||||
| Hind toe, | 4/12 | 4 1/2/12 | 4/12 | 4/12 | 4 1/2/12 | 4/12 | ||||||
| Its claw, | 4/12 | 3 1/2/12 | 3/12 | 3 1/2/12 | 4/12 | 3/12 | ||||||
| Middle toe, | 6/12 | 6 1/2/12 | 5 3/4/12 | 6/12 | 6 1/2/12 | 6/12 | ||||||
| Its claw, | 2 3/4/12 | 2 1/2/12 | 2/12 | 2 1/2/12 | 2 1/4/12 | 2 1/4/12 | ||||||
In a male shot at Charleston in January, the upper mandible has a prominent median line beneath, the palate is flat, the mouth 2 3/4 twelfths in breadth. The tongue is 5 twelfths long, emarginate and papillate at the base, slender, flattened, very narrow, tapering to a lacerated point. The œsophagus, a, b, c, is 1 1/2 inch long, of uniform diameter, being 1 1/2 twelfths in breadth. The stomach, d, e, is oblong, 5 twelfths in length, 3 1/2 twelfths in breadth, its muscles of moderate strength, the lower not distinct from the right; the cuticular lining longitudinally rugous, and of a dark brown colour. The intestine, f, g, h, is 8 inches long, the duodenum 2 twelfths in diameter; the cœca 1 twelfth long, 1 1/4 twelfth broad; the neck 9 twelfths long; the cloaca large, globular, 3 twelfths in diameter.
The trachea is 1 inch 3 twelfths long, of nearly uniform diameter, 1 1/2 twelfths broad; the lateral muscles strong, sterno-tracheal, and four pairs of inferior laryngeal muscles; the rings ossified.
ROCK WREN.
Troglodytes obsoletus, Say.
PLATE CCCLX. Adult Female.
This species was discovered by some of Major Long’s exploring party, and first described by Mr Thomas Say. My friend Thomas Nuttall, who had opportunities of studying its habits, during his recent journey in company with Dr Townsend, has assured me that they are very similar to those of the other Wrens. The figure in the plate was taken from an adult female, given to me by Mr Nuttall; and I have since then obtained two males. In my drawing the bird was represented on a stone, but for the reasons mentioned in my Introduction, my son Victor Gifford attached it to the drawing of the Winter Wren, so that it now appears perched on a twig, which, however, is not a common practice with this species.
“On the 21st of June,” says Mr Nuttall, “on the ledges of the bluffs which border the bottom of Hare’s Fork of the Siskadee (or Colorado of the West), I heard, and at length saw this curious Mountain Wren. Its actions are those of the Carolina species, Troglodytes ludovicianus. The old female (as I supposed) sat upon a ledge of rock at the head of a high ravine in the bluff, cocking her tail, and balancing herself, at the same time uttering a tshurr, tshurr, and té aigh, with a strong guttural accent, and now and then, when approached, like the common Short-billed Marsh Wren, Troglodytes brevirostris, a quick guttural tshe de de. It has also a shrill call at times, as it perches on a stone on the summit of some hill, again similar to the note of the Carolina Wren, occasionally interrupted by a tshurr. Among these arid and bare hills of the central table-land they were quite common. The old ones were feeding and watching a brood of four or five young, which, though fully grown, were protected and cherished with the querulous assiduity so characteristic of the other Wrens. They breed under the rocky ledges where we so constantly observed them, under which they skulk at once when surprised, and pertinaciously hide in security, like so many rats. Indeed so suddenly do they disappear among the rocks, and remain so silent in their retreat, that it is scarcely possible to believe them beneath your feet till after a lapse of a few minutes you begin to hear a low cautious chirp, and the next moment, at the head of the ravine, the old female probably again appears, scolding and jerking in the most angry attitudes she is capable of assuming. In the same rocky retreats they are commonly accompanied by a kind of small striped Ground Squirrel, like that of the eastern coast in many respects, but much smaller. These little animals, which are numerous, the White-chinned Buzzard, Buteo vulgaris of Richardson and Swainson, and the Raven frequently hover over and pounce upon. We met with this species as far west as the lowest falls of the Columbia, or within a few miles of Fort Van Couver, but among rocks and cliffs as usual.”