43 



is continued in the same lino with it without any dilatation, and 

 its limits are only recognisable when its internal surface is seen. 

 The lining membrane of the oesophagus exhibits at its commence- 

 ment (or pharynx) the usual assemblage of retroverted papilla', 

 after which it is smooth, and then rendered irregular by ruga', which 

 towards the termination of the tube fell into distinct narrow longi- 

 tudinal folds, evidently the consequence of a temporary state of 

 contraction at that part. As it passes into the proventriculus it 

 assumes the character of a mucous membrane, and also becomes 

 finely reticulate ; the orifices of the gastric glands being in the 

 interstices of the meshes. These glands are simple cylindrical 

 follicles dispersed over the whole cavity, but more closely aggregated 

 near the gizzard. The length of the proventriculus is 1 inch. 



"The gizzard is a spheroidal cavity, about \\ inch in diameter. 

 The muscular coat does not exceed half a line in thickness j the 

 lateral tendons are small but distinct. The horny lining membrane 

 is tough and hard ; it was stained of a deep yellow colour, and not 

 so readily separable from the muscular coat as I have observed in 

 other birds. The entrance to the gizzard is by an ample orifice, 

 and this, in connexion with the structure of the previously described 

 parts, perfectly accords with the regurgitating actions witnessed by 

 Mr. Broderip in Ramphastos erythrorhynchus, and which, being fol- 

 lowed by a repetition of the process of mastication, he aptly com- 

 pares to the act of rumination. The thin parietes of the gizzard, 

 corresponding to the omnivorous character of this bird, may render 

 in some cases additional mastication necessary ; and the powers of 

 the extraordinarily developed beak may in this way compensate for 

 the absence of the grinding structures so peculiar in the stomachs 

 of the true vegetable feeders. The pyloric orifice of the gizzard is 

 situated about a quarter of an inch from the cardiac entry, and is 

 only 3 lines in diameter. The stomach, if we include in this term 

 both proventriculus and gizzard., derives its nutrient fluid, as in man, 

 from two sources ; the one a vessel analogous to the coronary artery, 

 which comes off from the descending aorta ; the other an artery 

 from the hepatic, analogous to the gastro-epiploic ; but in this in- 

 stance the former vessel is remarkable for its superior size, in con- 

 sequence of having to supply materials for the extensive secretion 

 which takes place in the proventriculus. 



" The intestinal canal is 2 feet 1 inch in length ; it is 1-| inch in 

 circumference at the commencement, 2 inches at the termination, 

 and 1 inch at the middle, from which part it gradually widens to 

 both extremities. It is simple, being without caecal appendages, 

 corresponding in this respect to some carnivorous birds, as the Vul- 

 ture, King-Jisher, and Cormorant; to some insectivorous birds, as 

 the Nightingale, Woodpecker, and Hoopoe; and to some frugivorous 

 and granivorous birds, as Glaucopis, the Psiitacidai, Columba coro- 

 nata, and some other species of Pigeon. The mucous membrane of 

 the intestines presents extremely delicate villi, between 1 and 2 lines 

 in length, and repeats in a striking manner the peculiar downy cha- 

 racter of the external integument. These villi become in a very 



