12 BOTANY. 



doubtless because of the mechanical injury of the cells in making the 

 preparation, and the disturbing influence of the water in which it is 

 mounted. 



(c) In the stamen-hairs of Tradescantia Virginica the protoplasm 



Fig. 7. -An optical section of a cell of one of the stamen-hairs of Tradescantia 

 Vlryinica, after treatment with a solution of sugar. The protoplasmic sac has 

 partly collapsed, on account of the withdrawal of some of the interior water by the 

 sugar solution. At the bottom of the cell is the larsre nucleus ; in the strings and 

 bands of protoplasm there are streamings of the protoplasm, shown by the arrows. 

 After Hof meister. 



forms a rather thick layer over the inner surface of the cell-wall, and 

 in some part of this layer the nucleus lies imbedded. From the nucleus 

 and from various parts of the protoplasmic layer there pass to the 

 opposite side of the cell thicker or thinner bands and strings, always. 



