228 



DE. P. CHALMEES MITCHELL ON THE 



loop, displays in the unfolded condition a slightly spiral twist, and the shortening of the 

 caeca, a character shared with Eurypyga. The resemhlance to the Ralline type, how- 

 ever, is fairly strong. Meckel's tract is produced into a set of minor loops, of which 

 two represent " a," while " 6," with the diverticulum midway on the distal limb, and " c " 

 are normal, and the last is a supra-duodenal loop simplified in correspondence with the 

 reduction of the caeca. Bhinochetus has been compared with Scopus, but the character 

 of the tract does not support this comparison. In Bhinochefm there is no trace of the 

 twisted duodenum, the diverticulum is in the Gruiform position, and Meckel's tract ia 

 thrown into definite minor loops. 



EviiY-BYGUiM.— Eurypyga helias (fig. 47) departs stUl more from the other Gruifornies. 



Fig. 47. 



Intestinal Tratit of Eiirijpyja helias. Lettering as before. 



The duodenum resembles that of the other forms, but Meckel's tract is much more 

 archecentric, the greater part of it consisting of an irregularly folded gut swung at the 

 periphery of an oval expanse of mesentery. The large diverticulum, however, is not at 

 the apex of the tract, but in the typical Gruiform position on the distal limb of the axial 

 loop. The distal portion of Meckel's tract is a definite supra-duodenal loop with 

 bridging vein. The caeca are vestigial, and the rectum is long and nearly straight. 



Hkliornithid^. — In Ilelioruis fulica (fig. 4S) the typical Ralline or (iruiforra 

 characters again appear. The duodenum is simple and narrow. Meckel's tract displays 



