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Show 46 DROSERA ROTUNDIFOLIA. CHAP. III. it nearly equalled the cell in diameter; and a second sphere about half as large as the first, together with a few other minute ones, were formed. After 6 hrs. the fluid in which these spheres floated was almost colourless. ~fter 8 hrs. 35m. (always reckoning from the time when the solutwn was :£1-rst added) four new minute spheres had appeared. Next morning, after 22 hrs., there were besides the two large spheres, seven smaller ones, floating in' absolutely colourless fluid, in which some flocculent greenish matter was suspended. At the commencement of the process of aggregation, more especially in dark red leaves, the ?ontents of the cells often present a different app~aran_ce, as If the layer of protop:asm (primordial utricle) which lines the cells had separated Itself and shrunk from the walls; an irregularly shaped pur ple bag being thus formed. Other fluids, besides a solution of the carbonate for instance an infusion of raw meat, produce this same effect. 'But the appearance of the primordial utricle shrinking from the walls is certainly false;* for before giving the solution, I saw on several occasions that the walls were lined with colourless flowing protoplasm, and after the bag-like masses were formed, the protoplasm was still flowing along the walls in a conspicuous manner, even more so than before. It appeared jndeed as if the stream of prqtoplasm was strengthened by the action of the carbonate, but it was impossible to ascertain whether this was really the case. The bag-like mas os, when once formed, soon begin to glide slowly round the cells, sometimes sending out projections which separate into little spheres ; other spheres appear in the fluid surrounding the bags, and these travel much more quickly. That the small spheres are separate is often shown by sometimes one and then another travelling in advance, and sometimes they revolve round each other. I have occasionally seen spheres of this kind proceeding up and down the same side of a cell, instead of round it. The bag-like masses after a time generally divide into two rounded or oval masses, and these undergo the changes shown in figs. 7 and 8. At other times spheres appear within the bags; and these coalesce and separate in an endless cycle of change. After leaves have been left for several hours in a solution of the carbonate, and complete aggregation has been effected, the * vVith other plants I have often seen what appears to be a true shrinking of the primordial utricle from tlle wallf:l of the cells, cau ed by a solution of carbonate of ammonia, as lik wi. e follows from mechanical injurieR. CHAP. III. ,THE PROCESS OF AGGREGATION. 47 stream of protoplasm on the wall f ~i~ible; I observed this fact repe~t:~ t~e ce~ls c~ases to be Instance. A pale purple leaf was I y, d u~ Will give only one solution of one part to 292 of wa tpe ra caen d Iinn a2 fhe w drops of a purple spheres were formed in th ' rs. some fine the stream of protoplasm round ethupper cells of the pedicels d . · eu walls b · · ' IStinct; but after an additional 4 h . emg S~Ill quite many more spheres were formed th rs.t during WhiCh time distinguishable on the most caref 1 e s I~ea~ was no longer doubt was due to the contained gr~ eta~InatiOn; and this no with the spheres, so that nothing :u els ft ~ing ~ecome united ment of the limpid protoplasm could~ e . ~ Which the movefree spheres still travelled up and d e P~~cmved. But minute there was still a current. So it own e ce.lls, showing that b h . h t. was next mornmg f~ 22 Y w Ic Ime some new minute s h 'a ~;er hrs., these. oscillated from side to si'd e an dp ce hraesn gheadd thb e.e n formed '. proving that the current had not ceas d eir positions, protoplasm was visible. On th e ' tho~gh no stream of t ano er occasiOn h s ream was seen flowing round th II ' owever, a dark-coloured leaf, after it had been ele~: £-walls of ~ vigorous, stronger solution, namely, of one part f t;r 24 hrs. In a rather wat~r. This leaf, therefore, was not m~ e carbona~e ~o 218 of an Immersion for this lenO'th of t. . ch or at all lllJured by two grains to the ounce. a~d on b I~e 1~ the above solution of i~ water, the aggregat~d masses i~ng a terwards left for 24 hrs. dissolved, in the same manner many of the cells were renature when they re-expand af~~ ~ccu.rs with lea~es in a state of In a leaf which had been left for a2v~n:r~a~ght msec~s. part of the carbonate to 292 of water . In a solution of one plasm (formed by the self- dI'V l.S I.O n f' some spheres of proto- 0 a b l'J gently pressed beneath a c . ag- I m mass) were under a high power. The ov:I~g glass, .an.d then examined well-defined radiating fissur~s o~Ie now distinct!~ divided by fragments with sharp edges. ~nd -:re broken ~pInto separate In the larger broken sphere~ the cent~ !were solid to the centre. darker-coloured, and less brittle th Ia thart was. more opaque, alone being in some cases penetrate~; ~ exterwr; the latter of the spheres the line of . y t e fissures. In many inner parts was tolerably wel~eda~at~n between the outer and exactly the same ver al e ne .. The outer parts were of formed smaller spher!s .P a:d ~~rple I t~nt, a~ that of the last darker central core. ' ese a ter did not include any From these several facts we dark-coloured lea . may conclude that when vigorous ves are subJected to the action of carbonate of |