Holmes, TJie Reactions of Ranatra to Light. 315 



rear the anterior part of the body is carried high in the air and 

 the creature consequently easily loses its balance. 



At any time after Ranatra has ceased to feign death it can 

 be made to perform swaying movements in either direction, 

 although these may be combined with efforts at locomotion. By 

 carefully controlling the light, however, the tendency to loco- 

 motion may be largely checked. By moving the light around 

 the animal in a circle the tendency to turn back when the light 

 is behind may be made to balance the tendency to go forwards 

 when it is in front, and the animal simply sways around in its 

 tracks. 



Light seems to dominate entirely this creature's behavior 

 when the phototactic reactions are once started. It does not 

 manifest any fear or awareness of any object in its environment 

 save the light which it so strenuously seeks. Its excitement 

 increases the longer it is operated with, and after a time it may 

 be picked up without feigning death, or with only a momentary 

 feint. Not content with walking as rapidly as possible towards 

 the light, the insect begins to fly towards it, always doubling up 

 its fore legs in a curious manner before spreading its wings. 

 The wings are never used, however, until the creature has 

 sought for some time to reach the light by the ordinary meth- 

 od of locomotion. Their employment marks the attainment of 

 a high pitch of excitement in which the insect seems animated 

 by an uncontrollable frenzy which lasts until it is checked by 

 approaching exhaustion. 



If a Ranatra is placed on its back it often has considerable 

 difficulty in righting itself, and if near a light it will often walk 

 towards it without turning over. Locomotion under these cir- 

 cumstances is effected mainly by the anterior legs which are 

 flexed dorsally at the middle joint. These legs are not employ- 

 ed in ordinary locomotion, but when the creature is in an in- 

 verted position they are used with considerable dexterity. By 

 bending the legs dorsally the anterior end of the body is elevat- 

 ed, and by the alternate movement of these appendages the 

 insect walks along in a tolerably efficient manner. It will fol- 

 low the light around in this way in any direction. When out 



