DARWIN MEMORIAL. 89 



eyelids and mouth to the shedding of tears he has shown to 

 depend upon the necessity for preventing engorgement of the eyes 

 during screaming, an act originally useful solely to attract attention. 

 The steps by which he arrived at this conclusion are typical of his 

 method. Starting first with animals, he finds that their expressions 

 of grief are much less complex and various than those of man. 

 They are confined to noises, such as screaming, barking, whining, 

 in higher forms accompanied by changes in facial expression, par 

 ticularly by contraction of the muscles surrounding the eye. There 

 is a physiological necessity for this, as otherwise the expiratory 

 effort caused by screaming might engorge and rupture the small 

 ocular blood-vessels. By pressing on the lachrymal gland this 

 causes, in some of the higher animals, a flow of tears. What at 

 first was accidental, merely occasioned by the proximity of the 

 gland, becomes at last habitual, and the nervous force automatically 

 follows the line of its accustomed action, causing a flow of tears after 

 emotional excitement, even though no screaming take place. The 

 correctness of this view is supported by the fact that infants do not 

 shed tears until several weeks old, although they scream violently. 

 The functional activity of the lachrymal gland, in connection with 

 grief, is, therefore, later in phylogenetic development. The laws 

 of heredity and adaptation are found to be operating here, as else 

 where, in the domain of life; the supposed gap between the emo 

 tions of man and of other animals is successfully bridged over, and 

 another anthropocentric fallacy is consigned to the limbo of igno 

 rant superstitions. 



Many expressions of the lower emotions are found to be disfig 

 uring vestiges of acts useful to lower animals for offense and de 

 fense, or for obtaining food. These survive relics of the previous 

 history of our race as rudimentary organs are preserved long after 

 their use has ceased. The erection of the hair during fear is re 

 motely derived from the same cause that makes puss bristle when 

 attacked and the puff adder swell out when approached. Originally 

 used for the purpose of exciting fear in an enemy by an increase of 



