TEXTURES AND FLUIDS IN THE HIGHER ANIMALS. 211 



glands are engaged in some office bearing on the preparation 

 of the chyle in connection with lacteal absorption. If this 

 conjecture be well-founded, they belong to the same order of 

 organs with the mesenteric glands and the spleen. 



Brunner's glands are found solely in the duodenum. They 

 lie beneath the mucous membrane in the submucous tissue. 

 They are lobulated bodies, like detached pieces of the pancreas. 

 They are visible in the human intestine to the naked eye. 

 They have permanent ducts which pierce the mucous mem- 

 brane and open on its surface. If they have not the same 

 function as the pancreas, they may be regarded as bearing the 

 same relation to the pancreas which the labial and buccal 

 glands bear to the parotid and submaxillary salivary glands. 



TEXTURES AND FLUIDS, OR THE COMPONENT PARTS COMMON TO 

 THE BODIES OF THE HIGHER ANIMALS. 



The animal body, particularly in the higher orders of the 

 animal kingdom, is of a very composite but yet similar char- 

 acter. It consists, according to the received view in physio- 

 logy, of solids and fluids. The firmest and most compact of 

 the solids is bone, the softest or most watery of the solids is 

 the brain. The chief of the fluids is the blood, which, how- 

 ever, is hardly a fluid in the physical sense, being water 

 crowded with solid particles ; the nearest approach to a che- 

 mical fluid is the urine, which is water containing a large pro- 

 portion of saline matter in a state of solution. 



The living body is also represented as composed of several 

 connected systems, such as the vascular or circulatory system, 

 the respiratory system, the nervous system, the digestive sys- 

 tem, the urinary system, the reproductive system, the locomo- 

 tive system. These several systems are made up of organs, 



