54 ASA A. SCHAEFFER. 



left and moved away, a decided negative reaction. The light 



was shifted so that it lay directly ahead of the ameba 139. 



The ameba threw out three pseudopods on the left, but almost 



immediately retracted them. Another was sent out on the 



right, but it also was soon retracted. The ameba then moved 



forward, and in passing the blue light sent out a little pseudopod 



toward it 143. The ameba finally turned to the left and moved 



on. The ameba was shifted again with the blue light on the 



right 145. After the tip of the ameba had passed by the blue 



light it turned to the right. A small pseudopod was also sent 



out toward the light 148. The ameba was then shifted with 



the blue light lying directly in front 150. As the ameba moved 



forward a small pseudopod was thrown out into contact with 



the light 152. Then the ameba moved on. The ameba was 



shifted again with the blue light directly ahead 154 but a 



decided negative reaction set in. But when shifted again with 



the blue light ahead 158 the tip of the ameba turned away 



from, and then toward the light, but finally moved on in the 



original direction. The ameba was shifted again with the blue 



light directly ahead 162. The resulting behavior was indefinite. 



Another proteus was then brought into the field with a beam 



of blue light directly ahead 181. The ameba then threw out a 



pseudopod on the left and from this one another on the right, 



and from this last one still another on the right, so that the light 



was partially encircled. The ameba then moved off through a 



pseudopod on the left. The ameba was shifted with the blue 



light on the right 186. A pseudopod was thrown out on the 



right directly toward, and into contact with, the beam of light. 



The ameba then flowed away through another pseudopod on the 



right. The ameba was again shifted with the light lying on the 



right 190. Two pseudopods appeared on the right, one of 



which was directed toward the light spot. Both pseudopods 



were presently retracted and the ameba moved on to the left. 



Very peculiar behavior was observed when the ameba was shifted 



again 194. The behavior was at first negative, the ameba 



moving away to the right 195 but streaming was then reversed, 



and as the ameba passed by the light, two small pseudopods 



were sent out toward it 200. Thev were retracted however 



