(A) Tail of M. lessoni: two Central Rectrices shaded; (B) Tail of M. mexicanus: the Central Rectrices, not fully grown, are shaded; (C) Tail of M. lessoni, with stems of Central Rectrices partially denuded; (D) Tail of P. platyrhynchus, with Central Rectrices not symmetrical.
“The point is further elucidated by the examination of skins in our collection. We have a number of specimens of various species in which the central tail-feathers were growing when the birds were shot. The drawings now exhibited show some of them. Figure A represents the tail of a young Momotus lessoni in its first plumage. The central tail-feathers are here untouched; they merely show the reduction in the breadth of the web in the part which is subsequently denuded. Of this more anon. Figure B shows the growing feathers of the tail of a specimen of Momotus mexicanus; in this a few vanes have been removed from the left-hand feather. Figure C shows the process of denudation still further advanced. In all these three birds it will be noticed that the feathers in question have grown symmetrically, both being of nearly equal length. Figure D represents the tail of a Prionirhynchus platyrhynchus, where these feathers have not grown symmetrically, but the left-hand one has been developed sooner than the right-hand one. What has happened? The bird expecting to find two feathers upon which to operate has commenced to nibble not only the left central rectrix, but also the next rectrix on the right-hand side! But it seems to have not felt very certain about the state of its tail, for it has wandered off to one of the others, and commenced nibbling it also. When, however, the proper right-hand feather appeared, these mistakes have been discovered, and the work recommenced in the usual way. I can interpret in no other way the state in which the feathers on the right-hand side of the tail of this bird appear.”
THE EIGHTH FAMILY OF THE FISSIROSTRAL PICARIAN BIRDS.
THE ROLLERS (Coraciadæ).
These birds constitute a family of birds which are strictly denizens of the Old World, and are remarkable for their bright plumage. The vernacular name of Roller is given to them from their habit of mounting or “rolling” in the air. Canon Tristram, in describing the habits of the European species (Coracias garrula) in Palestine, writes as follows:—“On the 12th of April I reached Ain Sultan (Jericho) alone, and remained there in solitude for several days, during which I had many opportunities of observing the grotesque habits of the Roller. For several successive evenings, great flocks of Rollers mustered shortly before sunset on some dôm trees near the fountain, with all the noise but without the decorum of the Rooks. After a volley of discordant screams, from the sound of which it derives its Arabic trivial name of ‘Schurkrak,’ a few birds would start from their perch, and commence a series of somersaults overhead, somewhat after the fashion of Tumbler Pigeons. In a moment or two they would be followed by the whole flock, and these gambols would be repeated for a dozen times or more. Every where it takes its perch on some conspicuous branch or on the top of a rock, where it can see and be seen. The bare tops of the fig-trees, before they put forth their leaves, are, in the cultivated terraces, a particularly favourite resort. In the barren Ghor I have often watched it perched unconcernedly on a knot of gravel or marl in the plain, watching apparently for the emergence of beetles from the sand. Elsewhere I have not seen it settle on the ground. Like Europeans in the East, it can make itself happy without chairs and tables in the desert, but prefers a comfortable easy-chair when it is to be found. Its nest I have seen in ruins, in holes in rocks, in burrows, in steep sand-cliffs, but far more generally in hollow trees. The colony in the Wady Kelt used burrows excavated by themselves; and many a hole did they relinquish, owing to the difficulty of working it. But so cunningly were the nests placed under a crumbling treacherous ledge, overhanging a chasm of perhaps one or two hundred feet, that we were completely foiled in our siege. We obtained a nest of six eggs, quite fresh, in a hollow tree in Bashan, near Gadara, on the 6th of May. It is noticed by Russell among the birds of Aleppo.” The colour of the Common Roller is very beautiful, and we can well understand the significance of the Turkish name “Alla Carga,” or Beautiful Crow. The back is pale cinnamon-brown; the wing-coverts pale blue, excepting those on the edge of the wing, which are rich ultramarine; the quills brownish-black, deep ultramarine underneath; the secondaries with more blue on the outer web; the forehead white; the crown of the head and back of the neck pale blue; the lower back and rump ultramarine; the upper tail-coverts greenish-blue; the tail blackish-brown, the feathers blue at the base, the two centre feathers dull green; cheeks and throat pale blue, streaked with silvery blue; the under surface of the body pale greenish-blue. The total length is twelve inches. One curious feature about the European bird is that the outer tail-feather tends towards a point at the tip, as if there was an inclination to become elongated; and in Africa there is a species which actually differs from the European Roller only in having the outer tail-feathers elongated to an extent of several inches.
In Madagascar, that wonderful island which produces so many peculiar forms of bird life, there are found the Ground Rollers (Atelornis), extraordinary birds which live entirely on the ground, and only come out at dusk. Their flight is said by M. Grandidier to be very weak, so that the birds are never found above the lowest branches. They are rather local in their habitat, but where they do occur seem not to be uncommon. The Cyrombo Roller (Leptosoma discolor) is also a native of Madagascar, and has at first sight much the appearance of a Cuckoo, of which family of birds it was for many years considered to be a member. The head is extremely large in this bird, and the region of the nostrils densely plumed; but the latter, instead of being placed near the base of the bill, as in most Rollers, are situated nearly in the middle of the upper mandible. Messrs. Pollen and Van Dam give an interesting account of this bird in their notes on the “Birds of Madagascar”:—“The natives of the north-west of Madagascar give this bird the name of Cyrombo. It has the curious habit of hovering in the air, and uttering a very loud note, striking its wings against its body as it calls. This cry, resembling the syllables tu-hou, tu-hou, tu-hou, goes on increasing in force. Nowhere have we found this bird in greater numbers than in the forests in the neighbourhood of the bays of Boény and Jongony, in the south-western portion of the island of Mayotte. The racket that they make during the whole journey is truly wearisome. Although very active as criers, these birds are lazy and stupid. As soon as they are perched on the branch of a tree, they remain, so to speak, immovable, and in perpendicular position, so that it is easy to see them and knock them over. When seen in this position, they look like birds impaled. We suppose that they live in polyandry, because one always sees three times as many males as females; often we have seen three males in company with one single female, and all allowed themselves to be killed one after the other. In fact, when one is killed, the others do not fly away, but content themselves with merely moving from one branch to another. These birds live principally on Grasshoppers, but they devour also Chameleons and Lizards, which gives to their flesh a disagreeable odour, like that we observe in the Common Cuckoo. In preparing these birds we often found them with a species of large parasite of the family of the Ornithomyiæ, of a dirty green colour. We were never able to study the propagation of this bird; but while in Mayotte we saw an individual make a nest of rushes in the hole of a great ‘Badamier’ (Terminalia Catappa). These birds when they cry puff out the throat, so that this portion of the body has the appearance of a pendent bag. When wounded, they erect the feathers of the forehead and ears as well as those of the throat, all the while distributing well-aimed blows with the beak. The Cyrombo plays a great part in the chants and religious recitations of the Malagasy natives. The French colonists of Mayotte call this bird the ‘Parrot.’ It is common at Madagascar and Mayotte, and has, according to Mr. Sclater, been found in the island of Anjounan.”
BLUE ROLLER.
THE NINTH FAMILY OF THE FISSIROSTRAL PICARIAN BIRDS.—THE TROGONS (Trogonidæ).
These beautiful birds are found both in the Old World and the New, but are inhabitants of the tropical latitudes only. In Africa two species only are known, nor does another species occur until the coast of India is reached, and then in the forests of the peninsula and of the Himalayas there are some beautiful red-breasted representatives of the family, whence throughout the Malayan peninsula and the Sunda Islands some of the handsomest Trogons occur. But it is in America, from Mexico southwards, that the larger number of species is met with, no less than thirty-three out of a total of forty-six Trogons being peculiar to the New World. Their habits vary somewhat, as all the Old World members are insectivorous, while the American species principally feed on fruit, and only devour insects in a secondary manner. The Trogons may be distinguished not only by their broadened bill, but by the foot, where the first and second toes are turned permanently, two in front and two behind. This is a different arrangement to that of the Cuckoos and other climbing Picariæ, where the fourth toe is permanently or temporarily turned backwards as well as the first. The skin of these birds is remarkably thin and tender, so that their preparation is by no means an easy matter, and their appearance is also detracted from by a scantiness of plumage on the nape, where a great want of feathers takes place. Mr. Wallace, writing of the birds of this present family, remarks:—“As an instance how totally unable the Trogons are to use their feet for anything like climbing, we may mention that the Trogons of South America feed principally on fruit, which one would think they would get by climbing or walking after, if they could. But no; they take their station on a bare branch about the middle of the tree, and having fixed their attention on some particularly tempting fruit, they dart at it, seize it dexterously on the wing, and return to their original seat. Often, while waiting under a fruit-tree for Chatterers or Pigeons, have we received the first intimation of the presence of a Trogon by the whir-r-r of its wings as it darted after a fruit. It is curious that this habit seems confined to the Trogons of America. In the East I have never yet observed it, and in the numerous specimens I have opened, nothing has been found but insects. The African Trogons also appear to be wholly insectivorous.”
Again, in his “Naturalist in Nicaragua” (p. 122) Mr. Belt writes:—“The Trogons are general feeders. I have taken from their crops the remains of fruits, grasshoppers, beetles, termites, and even small crabs and land shells. The largest species, the Massena Trogon (Trogon massena), is one foot in length, dark bronze-green above, with the smaller wing-feathers speckled white and black, and the belly of a beautiful carmine. Sometimes it sits on a branch above where the army of ants are foraging below, and when a grasshopper or other large insect flies up and alights on a leaf it darts after it, picks it up, and returns to its perch. I sometimes found them breaking into the, nests of the termites with their strong bills, and eating the large soft-bodied workers, and it was from the crop of this species that I took the remains of a small crab and land shell (Helicina). They take short, quick, jerking flights, and are often met with along with flocks of other birds—Flycatchers, Tanagers, Creepers, Woodpeckers, &c., that hunt together, traversing the forests in flocks of hundreds, belonging to more than a score of different species, so that while they are passing over the trees seem alive with them. Mr. Bates has mentioned similar gregarious flocks met with by him in Brazil; and I never went any distance into the woods around St. Domingo without seeing them. The reason of their association together may be partly for protection, as no rapacious bird or mammal could approach the flock without being discovered by one or other of them; but the principal reason appears to be that they play into each other’s hands in their search for food. Creepers and Woodpeckers and others drive the insects out of their hiding-places under bark, amongst moss and withered leaves. The Flycatchers sit on branches and fly after the larger insects, the Flycatchers taking them on the wing, the Trogons from the leaves on which they have settled.”