Muscicapa Traillii.
PLATE XLV. Male.

This is a species which, in its external appearance, is so closely allied to the Wood Pewee, and the small Green-crested Fly-catcher, that the most careful inspection is necessary to establish the real differences existing between these three species. Its notes, however, are perfectly different, as are, in some measure, its habits, as well as the districts in which it resides.

The notes of Traill's Fly-catcher consist of the sounds wheet, wheet, which it articulates clearly while on wing. It resides in the skirts of the woods along the prairie lands of the Arkansas river, where alone I have been able to procure it. When leaving the top branches of a low tree, this bird takes long flights, skimming in zigzag lines, passing close over the tops of the tall grasses, snapping at and seizing different species of winged insects, and returning to the same trees to alight. Its notes, I observed, were uttered when on the point of leaving the branch. The pair chased the insects as if acting in concert, and doubtless had a nest in the immediate neighbourhood, although I was unable to discover it. It being in the month of April, I suspected the female had not begun to lay. Five of the eggs in the ovary were about the size of green pease. I could not perceive any difference in the colouring of the plumage between the sexes, and I have represented the male in that inclined and rather crouching attitude which I observed the bird always to assume when alighted.

I have named this species after my learned friend Dr Thomas Stewart Traill of Liverpool, in evidence of the gratitude which I cherish towards that benevolent gentleman for all his kind attentions to me.

The Sweet Gum, on a branch of which I have placed Traill's Fly-catcher, grows in almost every portion of the western and southern districts of the United States. It sometimes attains a great size, but is more commonly of moderate stature. Its wood is of little use. This tree is frequently found with a cork-like bark protruding in shreds from its branches.

Plate XLV. Adult Male.

Bill of ordinary length, depressed, tapering to a point, the lateral outlines a little convex, very broad at the base; the gap reaching to nearly under the eye; upper mandible with the edges acute, slightly notched close upon the tip, which is a little deflected and acute; lower mandible straight, acute. Nostrils basal, lateral, elliptical. Head and neck of moderate size. Body rather slender. Feet of moderate length, slender; tarsus compressed, covered anteriorly with short scutella, and longer than the middle toe; toes free, scutellate above; claws compressed, arched, acute.

Plumage soft and tufty; feathers of the head narrow and erectile. Wings of moderate length, third quill longest. Tail longish, slightly forked when closed, of twelve rather narrow, obtuse feathers.

Bill dark brown above, yellow beneath. Iris hazel. Feet brownish-black. The general colour of the plumage above is dull brownish-olive, the two rows of larger wing-coverts tipped with dull white. Throat greyish-white, as is a very narrow space around the eye; sides of the head and neck, and fore part of the breast, coloured like the back, but lighter; the rest of the under parts dull yellowish-white.

Length 5¾ inches, extent of wings 8½; bill along the ridge ½, along gap ¾; tarsus 7/12.

As already mentioned, this species bears a very close resemblance to Muscicapa acadica, and M. virens, more especially the former.

Muscicapa virens has the tail deeply emarginate, whereas in the present species that part is nearly even. The colouring is nearly the same in both, but M. virens is considerably larger.

Muscicapa acadica is also similarly coloured, but in it the whitish space about the eye is larger, the throat darker, the breast and abdomen lighter. The tail also is quite even. A decided difference exists in the bill, which, in place of being convex in its lateral outlines, is a little concave.

The Sweet Gum.

This species, which is the only one that grows in the United States, is distinguished by its palmate leaves, the lobes of which are toothed and acuminate, the axils of the nerves downy. In large individuals, the bark is deeply cracked. The wood is very hard and fine grained, but is now little used, although formerly furniture of various kinds was made of it. When the bark is removed, a resinous substance exudes, which has an agreeable smell, but is only obtained in very small quantity.