NUCLEOPLASMIC RELATIONS IN ARCELLA 1/ 



7. Reproduction of a uninucleate piece formed without an opera- 

 tion. Line 159. Arcellas in their natural en\dronment are 

 probably subjected to injuries ver>' much like those resulting 



Fig. 16 Arcella dentata. Outlines of the specimens in the pedigree shown 

 in figure 15. The drawings can be identified by comparing the following num- 

 bers and letters ^-ith those used in the pedigree. A = 10-27 (1). B = 8-24 E. 

 C = 14-31 (2). D = 12-27 (1). E = 11-27 (1). F = 9-26 E. (7 = 13-31 (2). 

 H = 14-a3 (2). X 207. 



from the operations described above, and it is also conceivable 

 that mechanical factors might interfere with normal fission in 

 such a way as to cause various abnormaUties. It was inter- 

 esting, therefore, to discover on January 18, 1918, that one of 



