1872.] DR. J. MURIK ON THE HORNED TRAGOPAN. 733 



manipulation it can be easily removed with the dermis, as is shown in 

 part, figs. 6, 7, & 14. In this respect it is analogous to the gorgeous 

 head- and throat-covering of the Cassowary, and to the varied dermal 

 coloration of the cheeks and wattles of many other birds. Micro- 

 scopic examination shows that the colour of the said parts in Ceri- 

 ornis is caused, as in the dark races of man, by a substratum of pig- 

 ment. The large pigment-cells, however, in the Tragopan, are of a 

 deep blue ; and according as they are in mass or more sparsely aggre- 

 gated, so is the intensity of the shade. On the throat, and especially 

 the broad strip of the wattle, the general outward colour is dark in- 

 digo, much deeper even in some parts by the addition of the black 

 filiform feathers ; but here and there are small oval spots of a brilliant 

 smalt, which shine like spangles among the feathering. 



(a) Pseudo-horns, and hoio erected. 



The cranial appendages or horns have superficially a casing or 

 layer of coloured skin precisely similar in composition to that I have 

 above described. This outer sheath is adherent, but loosely attached 

 to the parts beneath — and on maceration is easily removed en masse, 

 along with the dermal tissues of the forehead and face. Beneath it 

 there is a delicate and transparent enveloping layer of fibrous and 

 elastic tissue, intermingled with unstriped muscular bundles, and a 

 trace of the striped variety at the root — besides what appeared to me 

 as vessels, and probably nerve-fibres. 



Lastly, and deepest, is the long, conical, and pliant core, or horn 

 proper. This is solid, and composed throughout of firm elastic and 

 condensed fibro-cellular tissue, almost rivalling cartilage in density. 

 Externally it is nearly black in colour, but on cross-section is seen to 

 be a trifle lighter centrally. A thin transverse slice about the lower 

 third is translucent, and, held up to the light, exhibits a grey inte- 

 rior, gradating outwards to a narrow rim of deeper hue. The blackish 

 colour, however, increases higher up. Towards the upper third there 

 is a small, more or less oval, bluish-white circumscribed spot, situate 

 rather to one side of the centre, around which, from a sombre 

 brownish black, the tint merges into the deeper black. Quite at the 

 tip the light interior, or medullary-looking layer, is barely perceptible. 

 Under the microscope, with a low power, the exterior fibres are ob- 

 served to be predominantly circular in direction, those within chiefly 

 longitudinal and oblique. The deep colour results from a meshwork 

 of pigment-spots distributed everywhere, but are in greatest abundance 

 at what may be termed the cortical layer. Each pseudo-horn springs 

 direct from the cranial bones, at a roughened eminence between the 

 junction of the postfrontal and parietal. The base is pale-coloured, 

 and in all respects analogous to thickened periosteum. At this part 

 in our third specimen the diameter was 02 inch, tapering upwards 

 to a terminal point. Entire length 1 inch. 



As regards the mode of erection, this is evidently a muscular and 

 voluntary act, produced by the contraction and tension of a thin sheet 

 of muscular and aponeurotic fibres, derived from the pericranial 

 layer. At will, and during states of excitement, the bird has merely 



