124 PROTOPLASM 



the other hand, wherever these threads possess swellings 

 the reticulate structure can be plainly recognised. On 

 Plate XII. Fig. 2, a structureless thread of this kind is 

 depicted with a distinct reticular swelling. The coming to a 

 decision as to the ultimate structural relations of the thinnest 

 threads is hindered by the same difficulties which we have 

 already discussed for the finest pseudopodia of the Rhizopods. 



In the thin layer of protoplasm lining the internal wall 

 of the cell membrane as a continuous layer, the reticular 

 structure is very pale, and only to be made out with diffi- 

 culty, which is not to be wondered at when the excessive 

 thinness of this layer 1 is taken into consideration. Here 

 also, however, it is to be observed in surface view. After 

 treatment with suitable reagents it shows up very plainly. 

 Since, as we have seen, the places where the structure 

 is more distinct in life undergo no alteration through 

 the reagents employed, we have every right to consider the 

 reticular structure of the thin layer of protoplasm lining the 

 cell wall as a normal phenomenon, although it only becomes 

 perfectly distinct after treatment with reagents. 



In general my observations upon the structural relations 

 of the streaming protoplasm of the vegetable cell, both in 

 life and after treatment with reagents, prove its almost 

 complete agreement with that of the reticulose Rhizopods, 

 which have also a marked similarity in their mode of 

 movement. 



4. Observations on some Egg Cells 2 



In order to begin here also with observations on the 

 living object, I will first mention that the ripe ova of the 



1 Although I have as yet been unable to observe in optical section the 

 reticular nature of this layer of protoplasm clothing the wall, I am never- 

 theless of the opinion that it can only possess the thickness of one layer of 

 meshes. 



2 A few remarks upon some methods of investigation, employed in the 

 following studies, may not be out of place here. Coloration with so- 

 called iron-hsematoxylin was frequently employed and carried out by bringing 

 the objects or sections first into a light brown watery solution of ferrous 

 acetate ; and then, after washing out, they were stained in a J per cent 



