734 DR. J. MURIE ON THE HORNED TRAGOPAN. |~J une 18, 



to move the superciliary region forwards, as in the act of scowling, 

 and possibly lower the mandible a little, when the horn perforce must 

 be bent forwards, and become more or less erect according to trac- 

 tion. Undoubtedly there is no vascular erection, as in the case of the 

 wattle, presently to be mentioned. 



I know of no other such remarkable solid cranial appendage move- 

 able at will among the bird tribe, unless it be that of the Cotinga, 

 (Chasmorhynchus} and Horned Screamer (Palamedea). But in my 

 examination of Chasmorhynchus niveus the caruncle seemed soft and 

 spongy compared with the foregoing, suggesting the idea of vascular 

 erection, rather than a mere muscular act. 



Instead of a double whip-like comb, which may be the true homo- 

 logue, we may indeed liken the said head-organs in the Tragopan to 

 horns ; for although they have not the solidity of horn as in Rumi- 

 nants, they nevertheless present an intimate structure which suggests, 

 without being strictly, a horny constitution. 



(b) Intimate Structure of the Wattle. 



The wattle of Ceriornis satyr a is of a totally different nature, and in 

 most respects agrees with the same organ in other birds, — its brilliant 

 colour, magnitude, and mobility being matters rather of degree 

 than kind. Like the horns, it is fully developed only in the adult 

 male. As in the case of the testes in some birds, it is periodically 

 enlarged during the breeding-season, and then, in fact, only is in per- 

 fection. 



It is simply a duplication of the skin of the throat, containing, 

 like a single papilla or a larger fold, nerves, blood-vessels, retractile 

 and connective tissue. These increase in dimensions and complexity 

 as the bird arrives at maturity, and under the above-mentioned con- 

 ditions. 



In the male Jungle-fowl, as in the domestic breed of poultry, the 

 comb and the wattles are each a fleshy fibro- vascular organ, — the 

 former always firm and more or less erect, the latter at all times de- 

 pendent, though on occasions more fully distended with blood. In 

 the case of the Common Turkey- Cock the wattles and caruncula 

 dangle as loose appendages until moments of excitement, when the 

 vascular flow towards them produces the tumid phenomena. The 

 Tragopan's wattle differs from the preceding, inasmuch as it is thin, 

 more membranous, and contains a double sheet of either unstriped 

 muscular fibre or fibro-elastic tissue. The latter endows it with that 

 wonderful retractile capacity, withdraws it out of sight, and re- 

 tains it folded beneath the mandible, uuder ordinary circumstances, 

 or after it has been fully expanded. 



The vessels and nerves occupy chiefly the centre of the wattle. In 

 front and behind these are the thin transparent layers of the elastic 

 fibres and areolar tissue generally. These, again, on its two sides, 

 superficial and deep, are covered by the upper layers of the cutis and 

 epidermis, the blue-coloured portions coming in with the former. 

 The vessels form a true rete mirabile, and run in nearly straight pa- 



