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TIIK AMERICAN NATURALIST [Vol. LI 



(levc^lopiiiciit whicli point to cifects of tlie nucleus even on 

 tlie vi^il.lc .lift'crcntiation of tlie es>-,i>- before fertilization. 

 Ill llic s( a iircliiii. lor instniicc, tiiis dilferentiation is pre- 

 im'(I(m| hy the al»(>rpti()M into tlie nucleus of part of the 

 lli'id content of the r\ i(.pla-ni. altering- the chemical com- 

 position of the latl.-r an. I -ivatly increasino- the hulk of 

 the iMi.-icn^. Til. nu nil. ran. ■ ..f tlii^ enlar-ci nn<-lou> then 

 disM.lv^- an.l part ..f it^ .•..nP-nt^ 1:\ tli.'ir .-..(..r may be 

 trace.l to a .-l.-ar .-ap ..f llnl.l wlm-li lalor ,i:lx.'^ rlM- to the 

 .koh't..n ..I th.' .M.Mn...lcrm. Such abx.rptioiis and ming- 

 lini;- pr.)baM\- pla>- a large part in the reactions of 

 nncl(Mi> an.l c\topla>ni, either at the successive disap- 

 pcaran.-c- ol' tii.' nuclear membrane during mitosis or 



Xnclon^ an.l .-x'toplasm may certainly 1)0 regarded as 

 t'oiniln-' a reaction >\ stem analogous to that which might 

 e\l-l li.'l\\.'(n a -ei-ie- .)f cliemical su])<tauces (denning^, 

 1!IU). Tlu' .'yti-plaMU in turn is linked witli the exti-a 

 .-. llnlar milieu in a <|uite .-oniparable way and l'()rin> tlu^ 



Kvi.l.m.M.'.ui thi^ intern. -ti-.n i> a.-.nnnnlatin- A> an 

 example I may .|n..te tli.' \v..rk ..f ( 'anieron ami (ila.Ntone 

 on .-.Ol- other than ..varlan. an.l. to be sure, by the >tatic, 

 liiM<.l..iii.-al meth.xl. P.ut thev liax.' ..liM-rN.-d line pr.r 

 araticms and have concluded that th.' t..pla-m i^ x i^lbly 

 differentiat(Ml into two grades of en.h.j.la-m. The lir-t i- 

 next to the nucleus, is clear and ret'i'actl\ .'. Thl> is the 

 nascent material of the cell and is the tir-t \ isil)le stage 

 in the genesis of protoplasm. It is. the\ p.)siulate, a 

 derivative of the nucleus itself, an.l t.. the tui.-leus is 

 ascribed the final ela])oration of nutiativ.^ matei'ial which 

 ha^ b.-en in-e^te.l by the cvlopla^n. Thi^ na^.-ent endo- 



