. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 538 RUMINANTIA. ingesta are being macerated by the moisture secreted from the walls of the rumen (and probably also from the water taken in by the mouth, some of which may have entered the cavity), portions of the indigestible mass are transmitted into the second stomach for fur- ther maceration, and from thence into the demi-canal, to be moulded into the form of pellets, and returned to the mouth by a kind of reversed peristaltic action. The softened bolus, thus brought back into the mouth, is destined to receive a thor
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 538 RUMINANTIA. ingesta are being macerated by the moisture secreted from the walls of the rumen (and probably also from the water taken in by the mouth, some of which may have entered the cavity), portions of the indigestible mass are transmitted into the second stomach for fur- ther maceration, and from thence into the demi-canal, to be moulded into the form of pellets, and returned to the mouth by a kind of reversed peristaltic action. The softened bolus, thus brought back into the mouth, is destined to receive a thorough and deliberate remastication, and it is somewhat singular that this part of the process (called " chew- ing the cud") varies in different species. Professor Owen has the merit of showing that in the Cameline ruminants the bolus is triturated alternately from side to side, whereas, the action of the teeth in the horned Ruminantia, including the Giraffe, is always in one direction—it may be from right to left or left to right — occasioned by the rotatory motion of the jaw. The necessary reduction of the aliment having been accom- plished, it is again transferred to the stomach in a pulpy semifluid condition; but this time, instead of entering the first or second cavities, it passes directly along the (now closed) oesophageal groove into the manyplies. Here, the superfluous moisture is supposed to be absorbed before it is ultimately transmitted into the fourth stomach, in which organ the true digestive act remains to be fulfilled. The first, second, and third stomachs are incompletely developed in the newly born individual, where no chewing of the cud taking place, the food passing directly into the fourth ; in the Calf a peculiar organic acid is secreted by the lining membrane of the reed, which possesses the power of converting the albumen of milk into curd and u>hcy: this, in the prepared condition, is termed rennet. Concretions are frequently found in th
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