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ROBERT¡¡BROWN¡¡AND¡¡THE¡¡CELL¡¡NUCLEUS

In¡¡the¡¡year¡¡1833¡¡a¡¡further¡¡insight¡¡into¡¡the¡¡nature¡¡of¡¡the¡¡ultimate¡¡particles¡¡of¡¡plants¡¡was¡¡gained¡¡through¡¡the¡¡observation¡¡of¡¡the¡¡English¡¡microscopist¡¡Robert¡¡Brown£»¡¡who£»¡¡in¡¡the¡¡course¡¡of¡¡his¡¡microscopic¡¡studies¡¡of¡¡the¡¡epidermis¡¡of¡¡orchids£»¡¡discovered¡¡in¡¡the¡¡cells¡¡¡¨an¡¡opaque¡¡spot£»¡¨¡¡which¡¡he¡¡named¡¡the¡¡nucleus¡£¡¡¡¡Doubtless¡¡the¡¡same¡¡¡¨spot¡¨¡¡had¡¡been¡¡seen¡¡often¡¡enough¡¡before¡¡by¡¡other¡¡observers£»¡¡but¡¡Brown¡¡was¡¡the¡¡first¡¡to¡¡recognize¡¡it¡¡as¡¡a¡¡component¡¡part¡¡of¡¡the¡¡vegetable¡¡cell¡¡and¡¡to¡¡give¡¡it¡¡a¡¡name¡£


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¡¨As¡¡only¡¡one¡¡areola¡¡belongs¡¡to¡¡each¡¡cell£»¡¡and¡¡as¡¡in¡¡many¡¡cases¡¡where¡¡it¡¡exists¡¡in¡¡the¡¡common¡¡cells¡¡of¡¡the¡¡epidermis£»¡¡it¡¡is¡¡also¡¡visible¡¡in¡¡the¡¡cutaneous¡¡glands¡¡or¡¡stomata£»¡¡and¡¡in¡¡these¡¡is¡¡always¡¡doubleone¡¡being¡¡on¡¡each¡¡side¡¡of¡¡the¡¡limbit¡¡is¡¡highly¡¡probable¡¡that¡¡the¡¡cutaneous¡¡gland¡¡is¡¡in¡¡all¡¡cases¡¡composed¡¡of¡¡two¡¡cells¡¡of¡¡peculiar¡¡form£»¡¡the¡¡line¡¡of¡¡union¡¡being¡¡the¡¡longitudinal¡¡axis¡¡of¡¡the¡¡disk¡¡or¡¡pore¡£

¡¨This¡¡areola£»¡¡or¡¡nucleus¡¡of¡¡the¡¡cell¡¡as¡¡perhaps¡¡it¡¡might¡¡be¡¡termed£»¡¡is¡¡not¡¡confined¡¡to¡¡the¡¡epidermis£»¡¡being¡¡also¡¡found£»¡¡not¡¡only¡¡in¡¡the¡¡pubescence¡¡of¡¡the¡¡surface£»¡¡particularly¡¡when¡¡jointed£»¡¡as¡¡in¡¡cypripedium£»¡¡but¡¡in¡¡many¡¡cases¡¡in¡¡the¡¡parenchyma¡¡or¡¡internal¡¡cells¡¡of¡¡the¡¡tissue£»¡¡especially¡¡when¡¡these¡¡are¡¡free¡¡from¡¡the¡¡deposition¡¡of¡¡granular¡¡matter¡£

¡¨In¡¡the¡¡compressed¡¡cells¡¡of¡¡the¡¡epidermis¡¡the¡¡nucleus¡¡is¡¡in¡¡a¡¡corresponding¡¡degree¡¡flattened£»¡¡but¡¡in¡¡the¡¡internal¡¡tissue¡¡it¡¡is¡¡often¡¡nearly¡¡spherical£»¡¡more¡¡or¡¡less¡¡firmly¡¡adhering¡¡to¡¡one¡¡of¡¡the¡¡walls£»¡¡and¡¡projecting¡¡into¡¡the¡¡cavity¡¡of¡¡the¡¡cell¡£¡¡¡¡In¡¡this¡¡state¡¡it¡¡may¡¡not¡¡unfrequently¡¡be¡¡found¡£¡¡in¡¡the¡¡substance¡¡of¡¡the¡¡column¡¡and¡¡in¡¡that¡¡of¡¡the¡¡perianthium¡£

¡¨The¡¡nucleus¡¡is¡¡manifest¡¡also¡¡in¡¡the¡¡tissue¡¡of¡¡the¡¡stigma£»¡¡where¡¡in¡¡accordance¡¡with¡¡the¡¡compression¡¡of¡¡th

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