i.ARY N. CALKINS. 



much larger during the 48 hours after the operation and tin- 24 

 h<mrs after division, and attempted to divide on the thirtieth, 

 i he same day that its normal sister cell divided. The result of 

 this effort was a monster with two mouths and two vucuoles 

 l-ig. 20, /). On the first of February, or the fourth day after 

 tin- operation, the monster attempted a second division, this 

 time a double division, the result being one free individual and a 

 monster with three mouths (Fig. 20, /;, g). This free individual 

 \\.is smaller than the normal but it lived for 48 hours and died 

 during the process of division. It was detached from the parent 

 mass at the point corresponding to the upper end of Fig. 20, g. 

 The monster, meanwhile, continued to grow in size and on the 

 sixth day had two perfect Paramecium buds attached by their 

 posterior ends, and several papilla-like outgrowths which con- 

 tinued to grow like buds until on the ninth day well-defined 

 Paramecium cells were formed but remained attached to the 

 mass of protoplasm (Fig. 20, i, j). On the ninth day a second 

 normally formed cell (k) was detached, this being the upper one 

 figured in 20, i. This free form did not attempt to divide but 

 died before the end of 24 hours. On the twelfth day, still another 

 free form was given off (Fig. 20, n~), this being the individual on 

 the left side of Fig. 20, /. This one was small like all of the 

 detached forms, but appeared to be normal, living for 36 hours. 

 On the tenth and eleventh days the outlines of the previously 

 distinct paramecia buds on the parent mass, became obscure and 

 the individuals seemed to fuse with the protoplasmic mass while 

 the latter twisted and turned with the various ciliary movements. 

 At one period on the tenth day the mass became drawn out into 

 two main lobes (/) with a connecting strand between them and 

 appeared to be dividing, but the figure was due to the mechanical 

 pressure caused by the presence of a girdle of zooglcea about the 

 middle. When this girdle was removed with needles, the proto- 

 plasm returned to the more solidly massed state (m). A similar 

 constriction appeared on the thirteenth and fourteenth days and 

 /ooglu-a was once more removed and the obscure outlines o! 

 ghostly paramecia again appeared, no less than eight bizarre 

 forms stivtrhini; out from the parent mass at one time while six 

 more mouths could be counted on the general surface (Fig. 20, o). 



