LIVING MATTER IN "PROTOPLASM." 31 



" The fully developed protoplasmic body is constructed like a sponge, but, 

 at the same time, inclosed on all sides by the same substance which forms 

 the trabeculse of the sponge the trabeculae and the shell being the living 

 matter. 



11 An analysis of the observations of the living protoplasmic body teaches 

 us that there can be distinguished mainly three different appearances of the 

 net-like living matter namely, that of rest, that of active contraction, and 

 that of passive extension. 



"In the state of rest, as seen in a motionless amoeba, or immediately after 

 death, the granules are almost uniformly distributed throughout the pro- 

 toplasm, united with each other by slender threads, the bridges of living 

 matter. 



1 i In contraction, we observe an enlargement of the granules by shortening 

 of their uniting threads and approximation to each other. Nothing has been 

 added to the living matter and nothing lost from it ; only the distribution of 

 the plastidules has changed, leading to the narrowing of the net-work, and a 

 partial expulsion of the fluid formerly contained in its meshes. Contraction 

 is the active property of living matter, and on it are based the simple change 

 of shape and the locomotion of the whole organism. 



" Extension depends upon a decrease of size of the granules, with a 

 removal from each other and an elongation of the uniting threads at the 

 expense of the bulk of the granules, even to the disappearance of all 

 structure. The extension takes place in a passive manner ; the fluid con- 

 tained in the meshes of the living matter is pushed out toward the periphery, 

 and there leads to the formation of a protruding offshoot the hyaline flap. 

 At the beginning of the protrusion we still observe in the flap the presence 

 of structure, while at the highest point of extension the structure can no 

 longer be seen, because granules and threads have been elongated to their 

 utmost capability. We may compare this phenomenon to the extension of 

 glass rods, melted on a flame until the threads become so thin as to disap- 

 pear to the naked eye. 



" These three states of living matter explain to us not only the movement 

 of a simple protoplasmic lump, but also the action of the most highly developed 

 muscles, which, as I have demonstrated, are entirely identical in their 

 structure with the simple amoeba. Were the amoeba a sponge without an 

 inclosing layer of living matter on its surface, every contraction would lead 

 to an escape of the fluid, and no locomotion would be possible ; the pres- 

 ence of an outer, although very thin, layer of living matter is necessary to 

 the various movements of living protoplasmic bodies. 



" By adding a drop of glycerine to the creeping amoeba, or to any pro- 

 toplasmic body, we can bring about a fourth state of living matter, viz., 

 the highest degree of contraction, for which S. Strieker and I have proposed 

 the term ' tetanus.' The fluid of the protoplasm being suddenly extracted 

 by the glycerine, all granules flow together, forming a structureless lump of 

 much smaller size than that of the original corpuscle, without visible limits of 

 the single granules. A rehabilitation of the former net-like structure is pro- 

 duced by taking away the glycerine and adding water, without reestablishment 

 of motion. 



"All these changes of living matter can be directly seen under the 

 microscope. But we cannot observe the formation of a flat, extended layer 



