: ) 10 ii ANIM-.OOK OK PHYSIOLOGY. 



gravity, Tims, borrti 'and many other animals habitually drink uphill, 



and the same teat can he performed hy jui^lers. 



TIIK STOMACH. 



In man and t hose Mammalia which are provided with a : in" lc stomach, 

 il consists of a dilatation of t he alimentary canal placed het ween and con 

 Millions \\ il 1 1 t he (csophaiMis. which enters, its larger or card iac end on t he 

 one hand, and the small intestine, which commences at its, narrowed end 

 or p\ lorus, on I he oilier. It \aries in shape and si/.e accordini',' to its 

 state of distension. 



The Ifiunhnuils (o\, sheep, deer, etc.) possess \er\ romple\ stomachs; 

 in most of them four distinct cavities are to be distinguished ( l ; i" I'iil). 



I. The run iifh or l\iiin< H, a \ cr\ larrc ca\ il \ \\ In. 'h occupies I he car 

 diac end, and into \\hich lar^e <|uanlities of food are in the lirst instance 

 s\\ allowed \\ilh little or no mast icat i(n. ?. The /h'/int/tnii, or //onti/- 

 ((///> stomach, so called from the fact I hat its inn eon.-; memhrane i. 

 posed in a numherol folds enclosing hexagonal cells. ','>. The / 



JtfC 



I'h. I ;*, Sl,iin:i,-h..i IH-.-I. ,, .,- -.,.|.l.:ii-.n-.. K,t. ruinrn, /;, /. ivl i.-iiliiiii; 7V. ls.'ill.M-itnn, or 

 ; .l.iilioniMMiin. /),,., luo,r,-miiu; ,/. KI-,.,.V- froiii .i-s.-pliiiKUN I.. psnll.Tllim. (lluxlvy.) 



or Mitni/fifft'ti, iii \vhi-h I he mucous memhrane is MrrMU^ed in very promi- 

 nent longitudinal folds. -I. .l/>tnnnsnni. lu'cd. or lit'/tticf, narrow and 

 elongated, its mucous incmhrane hcin^ much more hi"hl\ vascular than 

 thai of the other divisions. In the process of rumination small portions 

 of the contents of the rumen and rclictilum are siiccessi\ el \ rejMirv.ilalcd 

 illlo the month, and there Miorouj-Jdv ma.licalcd and insalivated (chew 

 iii' ihccud): Miev are then a.",ain s\\ allon cd, heni", this lime directed hy 

 a L^roo\e (\\hich in the li;Mirc is seen runnin. i> , from the lower end of the 

 (esophagus) inlo lht> main plies, and thence into the ahomasuiu. It \\ill 

 thus he seen that the lirst, t \\ o stomachs (paunch and retieulum) have 

 ehicllv the- mechanical functions of storing and moistening t lie fodder: the 

 third (mainplies) prohahlx ads as a st raiucr. only allouin: 1 ; the linely 

 divide*! portions of food to pass on into the fourth stomach, when 1 the 

 ":i inc juice is secreted and the process of digestion carried on. The 

 mucous memhrane of the first three stomachs is lowly \ascular, while that 

 of tht' fourth is pulpy, glandular, and highly vascular. 



In some ot her animals, as the pi." . a similar (list i net ion obtains het w ecu 

 the mucous memhrane in dilTercnl parts of the stomach. 



