310 THE VITAL FUNCTIONS. 



several other amphibious animals, are provided 

 with large receptacles for the lymph, situated im- 

 mediately under the skin, and exhibiting distinct 

 and regular pulsations, like the heart. The use of 

 these lymphatic hearts, as they may be called, is 

 evidently to propel the lymph in its proper course 

 along the lymphatic vessels. In the frog four of 

 these organs have been found ; the two posterior 

 hearts being situated behind the joint of the hip, 

 and the two anterior ones on each side of the trans- 

 verse process of the third vertebra, and under the 

 posterior extremity of the scapula. The pulsations 

 of these lymphatic hearts do not correspond with 

 those of the sanguiferous heart ; nor do those of the 

 right and left sides take place at the same times, 

 but they often alternate in an irregular manner.* 



Chapter XIV. 



NERVOUS POWER. 



The organs which are appropriated to the per- 

 formance of the various functions conducive to 

 nutrition, are generally designated the vital organs, 

 in order to distinguish them from those which are 

 subservient to sensation, voluntary motion, and the 

 other functions of animal life. The slightest re- 

 flection on the variety and complication of actions 



* Phil. Trans, for 1833, p. 89. Muller has discovered similar 

 organs in the Toad, the Salamander, and the Green Lizard ; they 

 have been found in the Crocodile, and other Saurian reptiles, and also 

 in Serpents ; but not in any of the Chelonia. 



I 



