38 ON THE PLANT-CELL. 



1679. This work claims for him the title of the creator of scientific 

 botany. He is so accurate, and pursues so correct a method, that it was 

 a century before the time at which he wrote it, and at the present day 

 many so-called botanists do not know so much of plants as Malpighi. 

 He not only observed the cellular structure of plants, but maintained that 

 it was composed of separate cells, which he called Utriculi. 



Nehemiah Grew was secretary to the Royal Society at the time Mal- 

 pighi's work was publishing. He published his Anatomy of Plants in 

 1682 ; is much indebted to Malpighi. He first took up the wrong view 

 that the walls of cells are composed of fibres ; he also, by comparing the 

 cells of plants to the froth of beer, would appear to have thought that 

 they were mere cavities in a homogeneous substance, a view which was 

 afterwards supported by C. Fr. Wolff in his Theoria Generations, Halle, 

 1774. These false views have in modern times found supporters: the 

 first in Meyen, in his Physiology of Plants (vol. i. p. 45.) ; the second 

 in Mirbel and Unger. Meyen founds his notion of the fibrous struc- 

 ture of the cell-wall on having observed this structure in a new species 

 of orchid from Manilla. This is, however, not a singular appearance, 

 and an inquiry into the history of the development of the cells would 

 have dispelled the delusion. 



Mirbel has recently attempted * to support his view of the origin of the 

 cells as mere cavities in a homogeneous saline mass which he calls cam- 

 bium, by observations on the root of Phoenix dactylifera. This paper 

 is very incomplete, and the author has adopted a new system of nomen- 

 clature, which makes it difficult to follow him. Thus far I can say, that 

 no such division of continuity filled with a mucilaginous mass (his cam' 

 bium globuleux) between the bark (his region peripherique) and the 

 external portion of the woody bundles of the root (his region inter me* 

 diaire) exists as he describes. I have constantly found present cellular 

 tissue. Nor are the woody bundles of his region intermediaire sur- 

 rounded by this substance, but by cellular tissue. He is also deceived in 

 the nature of the contents of the cell by their intermixture with water. 



Unger (Bot. Zeitung, 1844) has published some observations on the 

 growth of the stem, in which he doubts whether the cytoblast is the origin 

 of the cell. In the instances where he has not observed the cytoblast in 

 the cells they had been evidently absorbed, whilst in those in which he 

 has seen and drawn them he has represented them to meet his own views. 



The views of Sprengel on the origin of cells from starch granules, the 

 similar ones of Du Petit Thouars and Raspail, and those of Turpin on the 

 nature of globuline, under which term he includes starch, mucus, colouring 

 matters, &c., do not deserve a scientific refutation. Other observations 

 on the origin of the plant-cell are unknown to me. Most botanists pass 

 the subject over in silence, although there can be no doubt that it forms 

 the introduction to a strictly scientific investigation of vegetable structure. 



In conclusion, I refer to Robert Brown (Observations on Orchideae, 

 Trans. Linn. Soc. 1833), who has here, as in so many other instances, 

 opened up a new path of inquiry. He first observed the cytoblast, as a 

 body, frequently present in plants: he did not, however, know its signifi- 

 cance in relation to the life of the cell ; he called it " nucleus of the cell." 



15. The free independent cells ot plants are developed in a 

 globular form. Their subsequent forms appear to depend on the 

 dissimiliar nutrition of individual parts of the cell -wall, and a con- 



* " Nouvelles Notes sur le Cambium," read at the Academy of Sciences, April, 

 1839. 



