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DR. GADOW ON THE ANATOMY OF PTEROCLES. [Mar. 21, 



centim. The second loop is nearly double the length of the first, 

 and has its apex doubled up into an irregular knot, as is characteristic 

 of the Gallinacei proper. The third loop is of about the same length 

 but straighter. The fourth loop is almost three times as long as 

 the duodenal one ; it is stowed away in the most ventral and lowest 

 part of the abdominal cavity, between the gizzard and the vent ; 

 throughout its whole length it is accompanied by the two caeca, 

 which are closely attached to this loop, as they are supplied by the 

 same branch of the mesenteric artery. The rectal part of the intes- 

 tinal tract is slightly wider than the ileum and the duodenum. 



The cwca (see fig. 4) are extremely well developed in Pterocles, 

 being IG centim. long, and are inserted at a distance of 15 centim. 

 from the anus. They are very wide and have very thin walls ; their 



Fig. 4. 



a, Cisca of Pterocles drcnarius ; b, Ca;ca of Syrrhaptes paradoxus (after Brandt). 



inner lining forms about 6 longitudinal slightly elevated folds. 

 (Prof. Parker says that the caeca of the Sand-Grouse have 12 longi- 

 tudinal folds, not 7 as have the Ptarmigans.) 



The cseca of Syrrhaptes, according to Brandt, are very wide and 

 long too, but differ from these organs of Pterocles in the shape of 

 their terminal parts, as shown in tig. 4. 



The liver of Pterocles I found to consist of two principal lobes — 

 the right lobe being about three times larger than the left one, 

 which exhibits on its inner side a small Spigelian lobe. The sharp 



