1872.] DR, J. MURIE ON THE HORNED TRAGOPAN. 735 



rallel lines from the root to the free extremity (see Plate LXI. fig. 14). 

 As far as my dissection warrants me in speaking, for I labour under 

 the disadvantage of the specimen not being injected, the arterial 

 supply is derived from the superior cervical plexus or division of 

 the carotid, which may be taken as such on its emergence from be- 

 tween the muscles of the neck. The veins are fewer, superficial, and 

 anteriorly situate. They run forwards towards the angle of the jaw, 

 and communicate with the jugular. 



The physiology of the deflection and retraction of the wattle in the 

 Horned Pheasant is identical with that of other vascular erectile 

 organs. Usually the passive contraction of the fibre and elastic mem- 

 brane is sufficient to retain the flaccid fold in place under the throat. 

 During the breeding-season, however, fibre, vessels, and skin develop 

 apace, or seem concomitantly and temporarily to increase, doubtless 

 by a stimulus of nervous force and respective vascularity. When the 

 period of excitement ensues, a rapid rush of blood is sent to the parts 

 both of the gular region and head generally. The innumerable 

 arterial channels of the rete mirabile are quickly filled ; and powerful 

 contraction of the neck-muscles follows, as may be inferred from the 

 jerking movements of the head, mentioned in the first section. 

 The blood thus poured into the wattle, per saltum, throws down the 

 wattle, and, from the thinness and transparency of its walls, produces- 

 the magnificent scarlet tint spoken of by observers. Erection is 

 maintained for a shorter or longer period, according as the muscles 

 exert their pressure and prevent the return of the flow of blood. The 

 veins, besides, being fewer in number, delay sanguineous return. 

 The excitement having passed, relaxation follows, and the blood slacks 

 to its normal standard. Meantime, by the contraction of the fibres 

 within the wattle, it resumes its former place almost without an 

 effort. 



4. Resume of the more important points. 



1. The male of the Tragopan shows characteristic traits during 

 the breeding-season, differing in several ways from allied forms — but 

 principally noteworthy on account of elevating a pair of cranial 

 appendages, and displaying momentarily a gorgeous membranous 

 wattle. 



2. In the female rudimentary horns, even in the young, are 

 found. 



3. The so-called horns, as likewise the wattle, pari passu, increase 

 with age, and are only fully developed in the adult male at the 

 breeding-season. 



4. Even in the adult male the wattle is usually folded beneath the 

 jaw, and almost hidden by the feathering. 



5. Pseudo-horns, supraorbital region, cheek, portion of lower jaw, 

 throat, and wattle are more or less clad with a bright blue skin, not 

 due to venous turgescence or congestion. 



6. The said coloration results from a pigment-layer and free 

 granules situate in the dermis. 



7. That which properly constitutes the horn is a black, solid, yet 



