310 KANSAS UNIVERSITY SCIENCE BULLETIN. 



Stimulus. Upon freeing the wings it takes a step or two, then 

 stops. Though the legs follow their normal order in walking, 

 they may first be lifted and flexed in a peculiar way before they 

 are placed on the ground. It is further shown, that coordina- 

 tion is not destroyed, in that the hopper alights in quite a nor- 

 mal manner after a hop, and when placed on its back turns 

 over in a perfectly coordinated manner, though seemingly ex- 

 hausted from the effort. It must be added that it, as well as 

 the normal hopper and crayfish, will remain on its back, as 

 if hypnotized, if placed there with greatest care and careful 

 handling. 



If the palps are touched with a blade of grass, the mandibles 

 and maxilhie begin to move, but no grass is bitten off, and 

 sugar-water or soaked raisins, w^hich normally are never re- 

 fused, are no longer tasted or swallowed. Pinching the palps 

 slightly causes them to move, and if acid is put on the palps 

 it is at once rubbed off by the front legs. If the hopper is 

 placed on a blade of grass held vertically, it will attempt to 

 climb upon it by taking one or two steps upwards, and will cling 

 there, but only for a short time, as it soon becomes exhausted 

 from the effort. If one foot is pressed it takes a step in the di- 

 rection of the non-stimulated side. Bethe observed that after 

 the brain was removed these animals fluttered their wings 

 rhythmically, but never rose higher than the level from which 

 they started ; but I have seen them fly much higher shortly 

 after the brain was destroyed. 



When all but a narrow strip of nerve tissue from which the 

 optic nerves arise is removed from the brain tissue, the insect 

 hops, Hies and walks incessantly for hours, keeping its head 

 close to the table, its abdomen high above it, and when it 

 alights from hopping, it seems to have lost all sense of equilib- 

 rium, or is completely exhausted. In this case the sight may 

 have been destroyed, and this fact may interfere with its equi- 

 librium, while inhibition of motion may be due to a constant 

 stimulus produced by the operation. Muscular weakness or 

 loss of tone may explain the abnormal position of the head re- 

 tained by the animal. Grasshoppers operated on in this way, 

 behave more like those arthropods that Bethe investigated, 

 since extirpation of their entire brain caused spontaneous and 

 prolonged activity. The above observations show that in the 



