1902 Encyclopedia > Touraco

Touraco




xTOURACO, the name, evidently already in use, under which in 1743 Edwards figured a pretty African bird, and presumably that applied to it in Guinea, whence it had been brought alive. It is the Cuculus persa of Lin-

White-Crested Touraco (Turacus albicristatus). After Schlegel.
naeus, and Turacus or Corythaix persa of later authors, who perceived that it required generic separation. Cuvier, in 1799 or 1800, Latinized its native name (adopted in the meanwhile by both French and German writers) as above, for which barbarous term Illiger, in 1811, substituted a more classical word. In 1788 Isert described and figured (Beobacht. Gesellsch. natuff. Freunde, iii. pp. 16-20, pi. 1) a bird, also from Guinea, which he called Musophagd violacea. Its affinity to the original Touraco was soon re-cognized, and both forms have been joined by modern sys-tematists in the Family Musophagidx, commonly Englished Plantain-eaters or Touracos, sometimes spelt Tourakoos.
To take first the Plantain-eaters proper, or the genus Musophaga, of which only two species are known. One about the size of a Crow is comparatively common in museums, and is readily recog-nized by having the horny base of its fine yellow bill prolonged backwards over the forehead in a kind of shield. The top of the head, and the primaries, except their outer edge and tip, are deep crimson; a white streak extends behind the eye; and the rest of the plumage is of a rich glossy purple. The second species, M. rossse, which is rare, chiefly differs by wanting the white eye-streak. Then of the Touracos—the species originally described is about the size of a Jay, and has the head, crest (which is vertically com-pressed and tipped with red), neck, and breast of a fine grass-green, varied by two conspicuous white streaks—one, from the gape to the upper part of the crimson orbit, separated by a black patch from the other, which runs beneath and behind the eye. The wing-coverts, lower part of the back, and tail are of a bright steel-purple, the primaries deep crimson, edged and tipped with bluish-black. Over a dozen other congeneric species, more or less resembling this, have now been described, and all inhabit some district of Africa; but there is only room here to mention that found in the Cape Colony and Natal, where it is known as the "Lory" (cf. vol. xv. p. 7, note 1), and, though figured by Daubenton and others, first differentiated in 1841 by Strickland (Ann. Nat. History, vii. p. 33) as Turacus albicristatus—its crest having a conspicuous white border, while the steel-purple of T. persa is replaced by a rich and glossy bluish-green of no less beauty. In nearly all the species of this genus the nostrils are almost completely hidden by the frontal feathers; but there are two others in which, though closely allied, this is not the case, and some systematists would place them in a separate genus Gallirex; while another species, the giant of the Family, has been moved into a third genus as Corythseola cristata. This differs from any of the foregoing by the absence of the crimson coloration of the primaries, and seems to lead to another group, Schizorrhis, in which the plumage is of a still plainer type, and, moreover, the nostrils here are not only exposed hut in the form of a slit, instead of being oval as in all the rest. This genus contains about half a dozen species, one of which, S. concolor, is the Grey Touraco of the colonists in Natal, and is of an almost uniform slaty-brown. A good deal has been written about these birds, which form the subject of one of the most beautiful monographs ever published —De Toerakds afgebeld en beschreven,—by Schlegel and Westerman, brought out at Amsterdam in 1860; wdiile the latest collected information is contained in an elaborate essay by Herr Schalow (Jour. f. Ornithologie, 1886, pp. 1-77). Still, much remains to be made known as to their distribution throughout Africa, and their habits. They seem to be all fruit-eaters, and to frequent the highest trees, seldom coming to the ground. Very little can be-confidently asserted as to their nidification, but at least one species of Schizorrhis is said to make a rough nest and therein lay three eggs of a pale blue colour. An extraordinary peculiarity attends the crimson coloration which adorns the primaries of so many of the Muscphagidae. So long ago as 1818, Jules Verreaux observed (Proc. Zool. Society, 1871, p. 40) that in the case of T. albicristatus this beautiful hue vanishes on exposure to heavy rain and reappears only after some interval of time and when the feathers are dry.
The Musophagidx form a very distinct Family of Prof. Huxley's Coccygomorphx, having perhaps the Coliidx and Guculidx as their nearest allies. Eyton pointed out {Ann. Nat. History, ser. 3, ii. p. 458) a feature possessed in common by the latter and the Musophagidx, in the "process attached to the anterior edge of the ischium," which he likened to the so-called " marsupial " bones of Didelphian Mammals. J. T. Reinhardt has also noticed (VidensJc. Meddels. Naturhist. Forening, 1871, pp. 326-341) another Cuculine character offered by the os uncinatum affixed to the lower side of the ethmoid in the Plantain-eaters
and Touracos ; but too much dependence must not be
placed on that, since a similar structure is presented by
the FRIGATE-BIRD (vol. ix. p. 786) and the PETRELS (vol.
xviii. p. 711). A corresponding process seems also to be
found in TROGON {q.v.). The bill of nearly all the species
of Musophagidx is curiously serrated or denticulated along
the margin, and the feet have the outer toe reversible.
No member of the Family is found outside of the conti-
nental portion of the Ethiopian Eegion. (A. N.)



Footnotes

Apparently the first ornithologist to make the bird known was Albin, who figured it in 1738 from the life, yet badly, as '1 The Crown-bird of Mexico." He had doubtless been misinformed as to its proper country; but Touracos were called " Crown-birds " by the Europeans in West Africa, as witness Bosnian's Description of the Coast of Guinea (1721), ed. 2, p. 251, and W. Smith's Voyage to Guinea (1745), p. 149, though the name was also given to the Crowned Cranes, Baleárica.

The fact of this colouring matter being soluble in water was inci-dentally mentioned at a meeting of the Zoological Society by Mr Tegetmeier, and brought to the notice of Prof. Church, who, after experiment, published in 1868 (Student and Intellectual Observer, i. pp. 161-168) an account of it as " Turacin, a new animal pigment con-taining copper." Further information on the subject was given by Monteiro (Chem. News, xxviii. p. 201; Quart. Jour. Science, ser. 2, iv. p. 132). The property is possessed by the crimson feathers of all the birds of the Family.







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