Size in locomotion 450 microns 

 Pseudopods cylindrical 



smooth ectoplasm 

 "main" pseudopod 



present 

 cross section 



circular 

 average number 



in locomotion, 



three 

 very numerous 



Crystals 



Fission 



all uniform trun- 

 cated bipyramids 



maximum size 



2-5M 



slower than 

 proteus 



Maximum time be- 

 tween divisions 20 days 

 Multinuclearity ' binucleate 



occasionally 



Nucleus, shape 



size 



General resistance 

 to same condi- 

 tions. 



Surface of 

 posterior end 



Effect of mechan- 

 ical stimuli 



Food cups 



Reaction to 

 carmine 



Distribution 



' biconcave disc, 

 never folded 

 40/x x iSju, 



j 



slight 



free from debris 



slightly responsive 

 Ismail 



readily eaten; 

 rejected in a 

 few minutes 



sporadic, small 

 numbers 



600 microns 



dorso-ventrally 

 flattened 



folded ectoplasm 



"main" pseudopod j 

 present 



cross section an 

 irregular oval 



average number 

 in locomotion, 

 five 



less than in 

 discoides 



all uniform trun- 

 cate d bi-pyra- 

 mids ; rarely a 

 few flat plates 



maximum size 



4-5/t 



average I division 

 in 48 hours at 

 20 C. 



8 days 



binucleate fre- 

 quent; tetranu- 

 cleate occasional 



biconcave disc, fre- 

 quently folded 



very great 



free from debris 



responsive 



large 



readily eaten ; 

 rejected in a 

 few minutes 



very common 



400 microns 



dorsoventrally 

 flattened 



smooth ectoplasm 



no "main" pseudo- 

 pod 



cross section 

 oval 



average number 

 in locomotion, 

 twelve 



relatively few 



at least four 



varieties present ; 



few perfect 



crystals 

 maximum size 



lO/j., 12^, 30^1 

 faster than proteus 



6 days 



binucleate very 

 rarely 



ovoidal 

 40/t x 32^ 



greater than 

 discoides 



carries debris 



very responsive 

 often enormous 

 eaten only occa- 

 sionally; often 

 retained for hrs. 

 sporadic, frequent- 

 ly in large 

 numbers 



are the different species of amebas so absolutely different, even 

 to the smallest detail? Why are the apparent resemblances and 

 similarities of their more generalized kinetic characters, such as 

 the formation of pseudopods, of ectoplasm, of crystals, of con- 

 tractile vacuoles, the general character of endoplasmic streaming, 



