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Show 1905.] ANATOMY OF LIMICOLINE BIRDS. 157 and notably different from that of the Columbae, or, indeed, of any other group except the Lari. The duodenal loop is simple and definite (text-figs. 24 and 25, A -B ); the portion of Meckel's tract proximal to Meckel's diverticulum (Div.) tends to be enlarged in such a way that the diverticulum is not at the apex of a loop as in Columbae or Passeres, but on the distal limb of a loop, which is short in the forms which are less specialised in this respect, such as the Chionidae, Glareolidae, Thinocoridae, GEdicnemidae, and the simpler Oharadriidfe (such as Numenius and Vanellus), Text-fig. 24. Diagram of intestinal pattern of Rhynclma capensis. A. Cut proximal end of duodenal loop. B. Distal end of duodenal loop. Div. Meckel's diverticulum. C. Origin of cseca. R. Cut end of rectum at cloaca. but which in other Charadriidae and Parridae (such as Scolopax, Himantopus, and Hydrophasianus) is elongated and spirally twisted. The portion of Meckel's tract between this and the duodenal loop is ill-defined in the simpler forms, but in others tends to be thrown into a definite narrow loop. The portion posterior to the diverticulum is in close relation to the colic caeca, which are long in the simpler forms (text-fig. 24, C.), but become |