. Elements of zoölogy. Zoology. 332 BACKBONED ANIMALS. food or cud is chewed twice before it is finally digested.* The molar teeth have two double, crescent-shaped folds, and, in biting, the incisors of the lower jaw are pressed. Ect. ' Fig. 356.—Stomach of a ruminant (sheep) : a?, oesophagus; Ru, paunch ; ret, honey-comb ; Ps, manyplies ; a, true digestive stomach or rennet; du} beginning of intestine. against the opposite and toothless gum of the upper. The stomach (Fig. 356), with few exceptions, is divided into four compartments : 1. The paunch, ru ; 2. The honey- * The grass, partly c
. Elements of zoölogy. Zoology. 332 BACKBONED ANIMALS. food or cud is chewed twice before it is finally digested.* The molar teeth have two double, crescent-shaped folds, and, in biting, the incisors of the lower jaw are pressed. Ect. ' Fig. 356.—Stomach of a ruminant (sheep) : a?, oesophagus; Ru, paunch ; ret, honey-comb ; Ps, manyplies ; a, true digestive stomach or rennet; du} beginning of intestine. against the opposite and toothless gum of the upper. The stomach (Fig. 356), with few exceptions, is divided into four compartments : 1. The paunch, ru ; 2. The honey- * The grass, partly chewed and mixed with saliva, is swallowed, and passes into the oesophagus ; the latter is continued into a tube with a long slit on its under side, whose lips fit closely, and are water-tight. The tube thus formed leads naturally to the third stom- ach, and here we see a wonderful provision. The coarse food as it is swallowed at first, from its size presses open the slit, and drops into stomach No. 1, or paunch, where it is mixed with water. From here it goes into stomach No. 2, or the honeycomb, where the polygonal spaces may serve to fashion it into pellets or cuds. Now, by a simultaneous contraction of the diaphragm and abdominal muscles, a cud is forced against the cardiac aperture of the stomach into the oesophagus, and so into the mouth, where it is chewed by the molar teeth, and again swal- lowed at last ready for digestion. As it passes down for the second time, we would perhaps expect it to press open the slit and drop into the first stomach again ; the second chewing, however, has reduced it to a pulp, so that it is now not large enough, and it passes along the tube over the slit and into the third stomach or manyplies, where it is strained ; then passing into the true stomach, where it is mixed with the gastric juice and Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloratio
Size: 2357px × 1060px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884
