286 C. D. SXYDER. 



The animals operated upon were kept in broad flat-bottomed 

 dishes. The floors of the dishes were kept covered with moist- 

 ened layers of filter paper. During resting periods the animals 

 were protected from the light of the room by being covered with 

 fresh leaves or moist filter paper, and by covering over the dishes 

 with towels. 



When these coverings were removed the animals, usually 

 asleep at the time, would sooner or later become aware that they 

 were out in the open. They would then become restless. In 

 their efforts to get under cover again one could note very easily 

 the manner of their progress. Movements were usually initiated 

 by the anterior parts turning to the one side and then to the 

 other several times and finally back to the tail, often moving 

 across it and twisting the body into a loop. During these move- 

 ments the posterior parts would lie motionless and apparently 

 helpless. After a number of these attempts at progressive loco- 

 motion the animal would start out straight ahead. The hind 

 parts being unresponsive, it would tug and pull with the fore-legs 

 in an effort to drag the helpless part along, and, in spite of the 

 great length of the body and tail, and the extreme delicateness 

 of the legs, the animal often succeeding in doing this. 



The results of this tugging and dragging of the hind parts, 

 while always the same, may be obtained by various methods, and 

 were observed in my experiments as follows : 



() Sometimes when the animals struck out in a forward direc- 

 tion and began to tug at the hind parts the hind-legs would begin 

 to assist before they ivere dragged in the least. Their movements 

 while slower than the fore-legs cooperated toi^ard forward loco- 

 motion, and, furthermore, were flexed and extended alternately, 

 that is, tlicy took forward steps alternately. 



(&) At other times no movements occurred in the hind-legs 

 until the hind parts had been dragged along for a distance. The 

 legs would then begin coordinate movements as described above. 

 Sometimes the legs happened to be extended back along the 

 sides of the tail and held up (surface tension of water and mucus 

 alone being sufficient to support the weight of the legs) so that 

 the toes did not touch the ground-surfaces. In such cases it was 

 noticed that the hind-legs remained irresponsive for a longer time 



