From February to July these Coursers live in pairs, and are usually met with running together over the arid sands of their desert haunts. Travellers tell us that they frequently dart along with such extraordinary rapidity that, like the spokes in a swiftly-turned wheel, their limbs become invisible, so that at a distance they present the appearance of legless bodies darting through the air; if pursued by man, it is not uncommon for them thus to avoid his approach for hours together. If very sorely pressed, they rise upon the wing to a moderate height, and hover for a time before recommencing their wild career. They will allow a rider to come nearer than a man on foot; but even when mounted, it is extremely difficult to get a shot at them, as their many enemies soon render them very timid. We learn from Bädeker that the eggs of this species are from three to four in number, short and broad, with a sand-coloured glossy shell, marked and dotted with a darker shade. These are deposited in a slight hollow in the ground amongst short grass or stones. We are unacquainted with further particulars respecting the nidification of the Cream-coloured Courser. THE TROCHILUS, OR CROCODILE WATCHER. The TROCHILUS, or CROCODILE WATCHER (_Hyas Ægyptiacus_, or _Trochilus_), differs in many essential particulars from the above group, to which, however, it is nearly allied. The body of this bird is compact, the neck short, and the head moderately large. The beak is not more than half as long as the head, compressed at its sides, and drawn in at the margins; the upper mandible rises gently from the base, and again curves downwards towards the tip; the lower mandible is straight; the leg is high, bare, and but three-toed; the wing, in which the first quill exceeds the rest in length, is so long, that it extends as far as the tip of the rounded tail. The secondary quills are also unusually developed. In this very beautiful bird, the top of the head, the broad cheek-stripes which unite at the nape, a wide stripe on the breast, and the long slender back-feathers are all black; the eyebrows, throat, gullet, and entire under side are white, shading into pale reddish brown on the sides and breast, and into brownish yellow in the region of the rump; the feathers on the shoulder and upper covers are pale slate-blue or grey; the quills, with the exception of the first (which has only a light border at the base of the outer web) are black in the centre and at the tip, the rest of the feathers being white, thus forming two broad stripes to the wings, which have a very fine appearance when fully spread. The tail-feathers are blueish grey tipped with white, and decorated with a black stripe. The eye is light brown, the beak black, and the foot light grey. The body is about eight inches and a half in length; the wing measures five inches, and the tail two inches and three-quarters. The female is but little smaller than her mate.