RENDEKIN". RH-I-TANT STARFISH EGGS NORMAL. 33J 



1 . Untreated eggs. (a) Unfertilized. The degree of post-maturation coagulation 

 varies here as in Lot A, but a larger proportion of eggs remain semi-transclucent, 

 an<l many are virtually unchanged in appearance. 



/ ,rtilized.- Mi ggs have formed membranes and cleaved or fragmented; 

 .1 mmitii-r form membranes but fail to cleave. A \>-\\ feeble blastula? are present 

 a fraction of i per o-nt.; no -urtaoe swimni- 



2. l:th>-r-tr-->ileii eggs. (In .\ vol. per cent, ether from i.oo tn 2..;_s P.M.) 



lizeil. Markt-d .\ t" i<i. All mature eggs are completely 



CoaKiila 1 - 'apart looking, without nu-rnhra:. 



/ -rtilizfJ. A large nun bla-iula? and gastrula? are present, many 



-wimining at the surface. \'i uni leaved eggs are present, though a good many 

 died in LgC8. M ' - 



The return ct tin- normal re-| >n-i\ cue to trrtili/atiini and 

 iiorinal j)o\v(.-r <>l <U-\ !< .pnn-nt i- \}\u< .1 u-i.iu-il \\ith a muni 



I ihr iinnii.il rate <>t" post-maturational i-\t<il\-i-. Thi^ iil>- 



SCrvation \va- made in -i\ "in i.t' nine e\])eriini-nt-, at dilYrrein 

 time- and \\itli ditterent l<t- ol in \\hiih rtlu-r-t real nieiu 



led tn marked Increase in the proportion <>| eggs under^oin^ 

 ta\oralle de\ elopmen t . In three <>! the earlier i-\[ierimein- the 

 lieha\ io|- of tin- ether- treated ii nter l ili/i d eggs \\a- imt nl>-er\ ed ; 

 Inn in .dl nl the BU - \\heie luith uli-er\ ation- \\eie made 



oiirurrenlly tin- \ 1 1 lal imi held. A- already mentioned, the 



decree .| impr< A eineiil ellei led |.y the ether ha- lueli \aiialile, 



in correspondence with the def f abnormality in the < In 



all ol the < asCS in \\hicli the improvement \va- derided, a- in -i H ne 

 ol those de-crilied aluAe, the nntreati'd mature eggs ;>ro\cil 

 lar-^eK refractory touard Imth r\ tol\ --i- .nid iCrtili/alion ; \\hik- 

 alter the treatment \\ith ether the eggs -ho\\i-d in hoth respects a 

 luhaxior ,i|iproai-hini; the 1 imrmal. In three other 1m- ot ab- 

 normal eggs treatment \\ith ether had no appreciable effecl 

 1'itlu-r in accelerating cytolysis or in increa-in;^ the proportion 

 ol l'a\orabl>- de\i'loi>in. ; \\hile in <>i in which a con- 



siderable proportion ol untreated CggS dc\eloped l'a\orably 

 about one third furmini; larxa tin- ether-treati'd t-y^> WCT( 

 ~ome\\hat /t.vv ta\orable than the untreated ; in thi- -i-ries the 

 unfertili/ed eggs, both tn.\itcil and untreated, -ho\\ed an ap- 

 pan-ntly normal -poiuanemis rytoly-i~. I'mbably the plasma 

 membranes of the-e eggs were over-suxvpiible rather than 

 under-susceptible to increase of permeability. The po--ible 

 e\i-tenre of both kinds of abnormalities must be reco-ni/ed. 



