480 PSYCHOLOGY. 



protect those organs from being too niucli gorged with 

 blood during the screaming fits of infancy, survives in 

 adult life in the shape of the frown, which instantly comes 

 over the brow when anything difficult or displeasing pre- 

 sents itself either to thought or action. 



" As the habit of contracting the brows has been followed by infants 

 during innumerable generations, at the commencement of every crying 

 or screaming fit," says Darwin, " it has become firmly associated with 

 the incipient sense of something distressing or disagreeable. Hence, 

 under similar circumstances, it would be apt to be continued during 

 maturity, although never then developed, into a crying fit. Screaming 

 or weeping begins to be voluntarily restrained at an early period of life, 

 whereas frowning is hardly ever restrained at any age."* 



The intermittent expirations which constitute laughter 

 have, according to Dr. Hecker, the purpose of counteract- 

 ing the ansemia of the brain, which he supposes to be 

 brought about by the action of the joyous or comic stimulus 

 upon the vaso- motor nerves. t A smile is the weak vestige 

 of a laugh. The tight closure of the mouth in all effort is 

 useful for retaining the air in the lungs so as to fix the chest 

 and give a firm basis of insertion for the muscles of the 

 flanks. Accordingly, we see the lips compress themselves 

 upon every slight occasion of resolve. The blood-pressure 

 has to be high during the sexual embrace ; hence the palpi- 



* Weeping iu childhood is almost as regular a symptom of anger as it 

 is of grief, whicli would account (on Darwin's principles) for the frown of 

 anger. Mr. Spencer has an account of the angry frown as having arisen 

 through the survival of the fittest, by its utility in keeping the sun out of 

 one's eyes when engaged iu mortal combat (!). (Principles of Psychology, ii. 

 546.) Professor Mosso objects to any explanation of the frown by its 

 utility for vision, that it is coupled, during emotional excitement, with 

 a dilatation of the pupil which is very unfavorable for distinct vision, and 

 that this ought to have been weeded out bj^ natural selection, if natural 

 selection had the power to fix the frown (see La Paura, chap. ix. § vi). 

 Unfortunately this very able author speaks as if all the emotions afliected 

 the pupil in the same way. Fear certainly does make it dilate. But 

 Gratiolet is quoted by Darwin and others as saying that the pupils con- 

 tract in anger. I have made no observations of my own on the point, and 

 Mosso's earlier paper on the pupil (Turin, 1875) I have not seen. I must 

 repeat, with Darwin, that we need more minute observations on this 

 subject. 



t Physiologic u. Psychologic des Lachens und des Komischen (Berlin, 

 1873), pp. 13 15 



