PROTOPLASM. 71 



of the latter in which we have such an elementary state of 

 things as in the Foraminifera. Even in the very lowest of 

 the plants the living matter of the embryo is bounded in the 

 adult by a definite wall, thus becoming what will be imme- 

 diately described as a " cell." 



Bioplasmic matter is colourless, transparent, and ap- 

 parently wholly destitute of structure. It has the property, 

 as shown by Dr Beale, of being deeply tinged by an am- 

 moniacal solution of carmine, whereby its presence is readily 

 detected. In all cases it has the power of spontaneous 

 movement, as may be well shown by an examination of 

 such a minute mass of bioplasm as is afforded by an Amoeba 

 or a mucus-corpuscle. In all cases the movements of bio- 

 plasmic matter, when unrestricted by any imprisoning en- 

 velope, are similar in kind to those of the ordinary Amoebae; 

 that is to say, the bioplasm has the power of extending 

 itself in all directions in the form of mutable processes, 

 which can be withdrawn at will. These movements are 

 often spoken of as instances of "contractility;" but the 

 term is, perhaps, hardly a suitable one, as it implies that 

 these movements are identical in kind with the contractions 

 of a muscle. Lastly, it has recently been shown that in 

 some cases minute masses of bioplasm have the extraordi- 

 nary power of passing, or, as it vr&t, flowing, through closed 

 membranes, without thereby losing their identity or form. 

 Thus it has been shown that the white corpuscles of the 

 blood have the power of passing through the delicate walls 

 of the capillary blood-vessels, and of thus obtaining access 

 to the tissues. 



The very minute particles which are known as "mole- 

 cules " do not require, as thought by some, to be considered 

 apart from bioplasm. The physical basis of life seems to 

 be structureless, and apparently homogeneous bioplasmic 

 matter. The simplest forms of living matter, however, at 

 an early stage exhibit extremely minute solid particles or 

 molecules, The first forms of life, also, which are developed 



