EFFECTS PRODUCED BY CUTTING PARAMECIUM CELLS. 59 



On the following day or fifteenth day after the operation, t\v<> 

 dead masses of protoplasm were found; the monster (Fig. 20, 0) 

 had divided in the middle and the two separated ma--e- evi- 

 dently licid n.t been physiologically balanced, and had died. 



In preparations made with the dead ma--c- no definite nuclei 

 could 1,.- (li-iin-ni-hed, ih,- matt-rial had evidently died during 

 tin- ni^ht and had liei-n dead too many hours for the preservation 

 of the nuclei. A large granular ma-- in one of the fragment.- may 

 ha\e I.e. -11 tin- remain- ol mi' lei perhaps aggregated into a mul- 

 berry mass as <le-. ribed l>y Balbiani. 



Gl ' i RAL. 



I'.all.iani'- coiiclu-ioii that / inn; doe- not regenerate as 



do oilier |iroto/.,a i- too -ueepii,. < nerali/at ion. A small 



p'-P enlace i.| cases do regenerate. Lilt the percentage xaries 



with dim-rent i In the e\|)eriment- hen- ..utlined. three 



diltereiit ^iaiit races "I I'urii n:fiium iudatum were u-fl. ( >ne 

 race, ln>m bracki-h \\.iter in R..-C. .1: approximately IO 



pel cent. "I regeneration-; another race, from New York. -a\e 

 approximately I per cent.: another race, al-> from New York. 



gave a relati\el\ hi'Ji percentage of regenerations, approximately 



JO per Cent., and in a foiinh race now under examination CVCTJ 



one r KM) per cent, regenerates. The method eim>l..\e<l by 



Halliiani \\a- l" in-lead of individual- one by one. 



This method made it impossible t,, determine iweniy-ioiir hours 

 atleru anl-. \\lu-iher the perte. i d-11- had not been cut at all. "i 



had been rut and had regenerated. 



I'roin my re-uli-it appear-, therefore, that diltereiil raie.-haM 

 dilten-nt p. \\ers >f te.-eiier.uion. ..r, st.iti-d in .mother \\a\ , h.i\e 

 \ar\im; decrees of \itality. This po\\er of regeneration is con- 

 nected in some wax . apparently, With the phy.sical make-up of the 

 protoplasm. In oi her forms of |irto/oa, notabK in Stcntor i man\ 

 observers, including lialbiani. ( iruber. Nu--!Miim. \\-rworn. 

 Tioua/ek. Lillie. l'o|ot't and other- . in Loxophyllum (Holni' 

 in StyliiH \rhin, O.\-y!rii'li<:. +{->; >t>s!<nniini , l : rontonia, Trachcloi,-r ( a, 

 Dili-ptns and Sputhidiitm, all of which, sa\-e Loxophyllum, 

 I ha\e experimented with in tin- connection, the protoplasmic 

 walls come together more or le-- ([iiirkh' alter the operation of 



