ALIMENTARY CANAL OF QUADRUMANA 



433 



330 



seat of true digestion ; the wider sacculated divisions have mainly 

 a preparatory and a receptacular function : a firm epithelium is 

 not continued into them from the oesophagus : the greatest cir- 

 cumference of the dilated stomach is 1 foot. The stomach of 

 the Semnopitltecus fascicularis is similarly complex but propor- 

 tionally smaller : as are also those of Nasalis larvatus and 

 Colobus ursinus ; in which, as in the 

 Semnopitheci, a narrow band of longi- 

 tudinal fibres, continued from the left 

 end along the greater curve, puckers 

 up the tunics into the larger sacculi, a 

 second band along the lesser curvature 

 contributing in a minor degree to this 

 complexity. 1 Evidence of the accumu- 

 lation and detention of vegetable food is 

 afforded here, as in Ruminants, by occa- 

 sional * beZOar ' Concretions. Obotw, Cercopithecus sttbwus. cxxu 



The stomach resumes its simple form in tailless apes: in which 

 the left end is less prominent than in Macaci, and the lesser 

 curvature is of greater extent ; the pyloric division is longer, 

 and the entire form less globular : in the Orang the pyloric 

 division shows a rather abrupt bend. 

 The lining membrane of the stomach 

 when in a moderately distended state 

 is devoid of ruga* in all Apes ; and 

 the small intestines are without 

 transverse folds of the mucous mem- 

 brane. The caecum in Catarhines 

 is always shorter than in Platy- 

 rhines, is usually wider and more 

 or less sacculated. In some species 

 of Cercopitheeus it is puckered up by 

 four longitudinal bands, of which 

 three are continued along the colon : 

 in most the csecum is more conical in shape than in Macacus, the 

 apex being narrower and more prolonged, e. g. Cere. Sabaus, 

 fig. 330. In Hylobates, fig. 331, the vermiform appendage re- 

 appears ; it is terminal, and in some species short ; but is more 



1 This type of quadrumanous stomach was discovered in an. undetermined kind of 

 monkey by Wurmb, in 1785 ; and, independently, by Otto, in a supposed Cercopi- 

 thecus in "1824, and described in cxxxvn": it was determined to be characteristic of 

 the natural group, including the genera Semnopithecns, Nasalis, and Colobus, in 

 cxxxvni", cxxxix", cxl", and cxli". 



331 



Caecum and vermiform appendage, 

 Uylobates. exxn'. 



VOL. III. 



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