222 



VETERINAEY PHYSIOLOGY 



The non-striped muscle in the framework of the spleen 

 undergoes rhythmic contraction and relaxation, and the 

 organ thus contracts and expands at regular intervals of 

 about a minute. 



These movements may be recorded by enclosing the organ 

 in an oncometer, a closed capsule connected with some form of 

 recording apparatus. 



The movements are controlled by fibres leaving the spinal 

 cord chiefly in the 6th, 7th, and 8th dorsal nerves of both sides. 

 Strong stimulation of these causes contraction. 



B. LYMPH 



Characters of Lymph. The lymph is the fluid which plays 

 the part of middleman between the blood and the tissues. 

 It fills all the spaces in the tissues and bathes the individual 

 cell elements. These spaces in the tissues open into vessels 

 the lymph vessels in which the lymph flows and is conducted 

 through lymph glands and back to the blood through the 

 thoracic' duct (see fig. 107, p. 225). 



Lymph varies in character according to the situation from 

 which it is taken and according to the condition of the 

 animal. 



Lymph taken from the lymph spaces e.g. the pericardium, 

 pleura, or peritoneum is a clear straw-coloured fluid. It has 

 little or no tendency to coagulate. Microscopic examination 

 shows that it contains few or no cells any cells which may 

 exist being lymphocytes. In reaction it is alkaline. The 

 specific gravity varies according to its source, being lowest 

 when from the limbs and highest when from the liver. 



Apparently the cause of the non-coagulation of such lymph 

 is the absence of cells from which thrornbokinase may be set 

 free. If blood or white corpuscles be added to it, a loose 

 coagulum forms. 



If the lymph be taken from lymphatic vessels after these 

 have passed through lymphatic glands, it is found to contain 

 a number of lymphocytes, and it coagulates readily. 



Chemically, lymph resembles blood plasma in which the 

 proteins are in smaller amount, but the inorganic salts in 



