ALIMENTARY CANAL :{.", 



the so-called bursa Fabricii. GADOW, in a recent work ! upon 

 this region of the alimentary canal, recognises three cham- 

 bers in the cloaca. Above, and separated by a constriction 

 from it, is the coprodseum, into which the rectum opens ; 

 this is divided by a constriction from the middle chamber, 

 or urodaeum, which receives the genital and urinary ducts ; 



FIG. 21. CLOACA OF Cliauna derbiuna LAID OPEN FROM IN FRONT. 



, rectum ; b, orifices of ureters ; //, genital papillae ; c, fold separating coprodieum from 

 urodaeum : </, fold separuthifr urodseum from proctodaeum ; e, opening of /, bursa 

 Fulirieii. (After FORBES.) 



then follows the proctodseum, of which the bitrsa Fabricii 

 is a diverticulum. 



The bursa Fabricii has been chiefly investigated by 

 FORBES 2 and WENCKEBACH. 3 It is a dorsal diverticulum of 

 the proctodseum, and therefore has nothing to do with the 



1 ' Remarks on the Cloaca and on the Copulatory Organs of the Amniota,' 

 Phil. Trans, vol. clxxviii. p. 5. 



- ' On the Bursa Fabricii in Birds,' P. Z. S. 1877, p. 304. 



3 ' De Ontwikkeling en de Bouw der Bursa Fabricii,' Inaucj. Diss. Leyden 

 1888. See also E. RETTERET, ' Contribution a 1'Etude du Cloaque,' &c., J. de 

 VAnat. xxi. 1885, p. 369. 



D 2 



