INTER-PROTOPLASTIC CONNECTIONS. 



457 



Intercellidar Connection of Protoplasts. In conclusion, we 

 will make use of our strongest objectives in order to approach a 

 problem the solution of which is of the greatest possible importance 

 to a collective conception of the vegetable body. This relates to 

 a reciprocal inter-connection of the protoplasmic cell-bodies of 

 the plant, of such a kind that they form a single, continuous whole. 

 The secondary cortex of dicotyledonous plants provides the most 

 favourable objects for this study, and amongst these we select 

 specially the Buckthorn, Rhamnus Frangula. From a part of a 

 stem, at least f inch thick, we first remove the periderm with the 



V .3 



FIG. 160. Tradeseantia Virgin ica. Nuclei of older intern odes in direct division. 

 .-1 , during life ; />, after treatment with acetic methyl-green ( x 540). 



razor, and then prepare delicate tangential longitudinal sections 

 through the green cortex. We will first make use of these sections 

 in order to inform ourselves as to the structure of the secondary 

 cortex, and for this purpose examine them in water. We direct 

 our attention primarily to the chlorophyll-containing bast-paren- 

 chyma, which we see to be composed of rectangular cells, chiefly 

 elongated tangentially. These cells have more or less strongly 

 thickened walls, penetrated by broader or narrower pits, in part 

 so narrow that they are difficult to distinguish. All these pits are 

 simple or " unbordered ". Besides the bast-parenchyma, we shall 

 specially note the long bast-fibres, and the spindle-shaped cross- 



