154 PRINCIPLES OF PHYSIOLOGY 



Curious rhythmical movements of the spleen 

 have been studied, and on a tracing of these 

 movements large waves occur about once in a 

 minute ; on these there are smaller waves due 

 to respiratory movements ; and on these, again, 

 still smaller waves, corresponding to the beats 

 of the heart. This rhythmic mechanism 

 must assist in the transmission of blood 

 through the organ. It is influenced by special 

 nerves. 



84. The ihymus gland, found in the chest 

 behind the breastbone, is a blood gland of 

 later foetal and early infantile life. Very 

 little is known of its functions. 



85. It is suspected that other organs, 

 having definite functions with which we are 

 acquainted, have also hidden functions little 

 understood. In this way the kidneys may 

 have a hidden function ; at all events removal 

 of a kidney, or even a portion, has been found 

 to affect the general nutrition of the body. 

 In some similar way the generative organs, 

 ovary and testis, especially during their 

 development, may influence the nutrition of 

 other parts. This is seen to a marked degree 



