The Instinct of Feigning Death 205 



exhibited in different species in all stages of develop- 

 ment from a momentary feint to a condition of in- 

 tense rigor lasting for over an hour. 



Among the vertebrate animals death-feigning has 

 been observed only rarely in the fishes. In the Am- 

 phibia it is not exhibited in the striking way it oc- 

 curs in insects and spiders, although frogs and toads 

 may be thrown by the proper manipulation into an 

 immobile condition more or less resembling it. A 

 phenomenon apparently related to the death feigning 

 of insects has long been known in certain reptiles. 

 Darwin in his Journal of Researches describes a 

 South American lizard which when frightened "at- 

 tempts to avoid discovery by feigning death with out- 

 stretched legs, depressed body, and closed eyes; if 

 further molested it buries itself with great quickness 

 in the loose sand." The Egyptian snake charmers 

 by a slight pressure in the neck region are able to 

 make the asp suddenly motionless so that it remains 

 entirely passive in the hands of the operator. And 

 similar phenomena have been found in other spe- 

 cies. 



In birds the instinct crops out only here and there. 

 A few summers ago when on the island of Peni- 

 kese I was somewhat surprised to find the instinct 

 well developed in the young terns which were 

 hatched out in abundance on the hillsides. For a 

 short time after being hatched the little downy 

 fellows betray no fear of man and will cuddle un- 



