CHAPTER III. 



Examination of the Matured Framework of Cell- 

 membrane in Plants. 



1800-1840. 



There is no sharp line of division between the 18th and the 

 19th centuries; the phytotomists who appear on the scene 

 during the first years of the new century are scarcely more 

 successful than Hedwig and Wolff; careful and judicious 

 interpretation of their own and others' observations is still rare, 

 and they are often misled by preconceived opinions. 



In one respect indeed a very great improvement appeared 

 with the commencement of the 19th century; the number 

 of phytotomists working contemporaneously, checking and 

 criticising one another, became all at once much larger. 

 Hitherto ten or twenty years had intervened between every 

 two works on phytotomy ; but in the course of the twelve 

 years after 1800 nearly as many publications followed one 

 another, and scientific discussion enlivened enquiry. Now 

 we meet with a Frenchman for the first time in the field 

 of phytotomy, Brisseau Mirbel, who brought out his ■ Traite 

 d'Anatomie et de Physiologie Vegetate' in 1802, and raised 

 a series of questions in the discussion of which several German 

 botanists, Kurt Sprengel (1802), Bernhardi (1805), Treviranus 

 (1806), Link and Rudolphi (1807), at once took part. It was 

 a step in advance and one affecting all botanical studies, that 

 with the exception of Rudolphi all these men, like Hedwig 

 before them, were botanists by profession ; it was at last felt 



