IJB MR. F. E. BEDDARD ON THE [Apr. 6, 



1. On some Points in the Anatomy of Chautia chavaria. By 

 Frank E. Beddard, M.A., F.B.S.E., F.Z.S., Prosector 



to the Society. 



[Received March 15, 1886.] 



Prof. Garrod has contributed to the ' Proceedings ' of this Society 

 some notes upon the anatomy, more particularly of the soft parts, of 

 Chaima derhiana '. The recent death of one of the Society's specimens 

 of C'hauna chavaria has enabled me to supplement Prof Garrod's 

 observations by some notes on the structure of the second species of 

 C'hauna. As might have been expected, there are no great differences 

 between the two species; and with the exception of the colic caeca 

 and the distribution of tlie tracheal muscles, all the statements made 

 by Garrod apply equally well to the present species ; with regard to 

 tiie visceral anatomy I am not able to institute a detailed compari- 

 son between the two species, since certain of the facts which I 

 shall describe in the present paper have not been referred to by 

 Garrod in his account of Chaima derhiana. To these facts I have 

 paid particular attention in order to render more complete our know- 

 ledge of this interesting bird. 



Air-sacs, i|c. — On opening the body-cavity it was seen to be 

 completely separated into a right and left half by a vertical septum 

 attached above to the sternum and the ventral wall of the abdomen, 

 and below to a horizontal fibrous septum which will be presently 

 described. This vertical septum anteriorly separates the two lobes 

 of the liver and runs as far forward as the pericardium ; it 

 corresponds to the umbilical ligament, a structure which has not 

 usually so great an extent in birds ; more generally the umbilical 

 ligament only extends as far hack as the gizzard and terminates in a 

 semicircular free posterior margin. In Chauna this vertical ligament 

 bears a blood-vessel which joins the portal system anteriorly and 

 posteriorly divides into two trunks, one of which passes further 

 hack than the other ; this vessel is situated near the dorsal attach- 

 ment of the septum. The horizontal septum is an extremely thick 

 brown-coloured membrane which passes across the abdominal cavity 

 from side to side, and completely covers the coils of the intestine, 

 being attaolied laterally to the walls of the abdomen. This tough 

 brown membrane corresponds to a structure described hy Weldon 

 (P. Z. S. 1883, p. G40) in the Storks, and by myself (P. Z. S. 1885, 

 p. 841) in the Cranes and other birds. This horizontal membrane 

 when it reaches the gizzard splits into two layers which form a 

 complete covering to that organ ; between it and the gizzard, on the 

 inferior surface of the latter, are numerous air-spaces which were 

 easily distended by inflating the air-sacs. 



The relations of the abdominal viscera are therefore, so far as the 

 presence of this horizontal septum is concerned, indicative of an 

 affinity with the Storks and (Jranes, and more particularly with the 



' ' Collected Papers,' p. 318. 



