66 



Scientific Proceedings (iio). 



if the parallelism between the two conditions is as we surmise, 

 one would expect the greater severity of symptoms which occurs 

 in human beings. 



30 (1612) 



Dissection and injection studies on the Amoeba. 



By Robert Chambers. 



[From the Department of Anatomy, Cornell University Medical 

 College, New York City.] 



The species used was Amoeba proteus. By means of a micro- 

 pipette liquids of various kinds were injected and the effect noted. 



Oils form spherical droplets which are carried about in the 

 cytoplasmic currents. A large drop is usually expelled. Imme- 

 diately on being extruded the drop tends to flow over the surface 

 of the Amoeba thus partially engulfing it. 



Distilled or spring water diffuses through the granular endosarc 

 diluting it. The dilution is followed by a contraction of the endo- 

 sarc and the massing of a hyaline fluid between the endosarc 

 and the external pellicle of the Amceba. This dilates the area 

 usually termed the ectosarc. The fluid soon accumulates on one 

 side of the Amoeba in the form of a blister which is ultimately 

 pinched off. 



A number of acid indicators were injected. The color reactions 

 showed that the protoplasm of the Amoeba is more acid than its 

 environment. Upon death the colors change to those character- 

 istic of the surrounding medium. 



The difference in behavior of living protoplasm to "basic" 

 and to "acid" dyes is striking. The "basic" dyes used were all 

 chlorides of colored basic radicles and the "acid" dyes, potassium 

 or sodium salts of colored acid radicles. In every case the "basic " 

 dyes had a coagulating and the "acid" dyes, a liquefying effect on 

 the protoplasm. 



In the case of the "acid" dyes, when the effect is local, the 

 healthy non-colored portion of the endosarc shrinks away from 

 the colored liquefied area. This liquid accumulates under the 

 pellicle in the form of a blister and is ultimately pinched off. 



