52 BOTANY paet I 



interior, on the other hand, the hyaloplasm is thin and fluid-like, it 

 contains numerous granules, and is then designated granular plasm. 

 In the granular plasm will be found the nuclei of the various amoebae, 

 from which the plasmodium has been formed. 



The granular plasm of plasmodia exhibits streaming movements, as 

 of different commingling currents, and affords a good example of the 

 internal movements commonly shown by living protoplasmic masses. 

 Thus, in addition to the flagellar or ciliary movements, by means 

 of which, as was observed in the swarm-spores of Chonddodcniui, a 

 change of position is effected through the whip-like motion of fine 

 cytoplasmic threads, and the creeping amoeboid movements, such 

 as were also exhibited by Chrondrioderma in the amoeba stage of 

 its development, there may also be recognised, as in the case of the 

 Plasmodium, internal protoplasmic movements. A plasmodium is 

 also capable of creeping movements. It sends out new protrusions, 

 and draws in others previously formed. If two protrusions meet, 

 they unite to add a new mesh to the network of the plasmodium («, 

 Fig. 52). The viscous structureless superficial pellicle of hyaloplasm 

 exhibits only creeping movements, while internal protoplasmic move- 

 ments also take place in the more fluid granular plasm. Thus the 

 granular plasm is continually flowing in irregular currents, alternately 

 towards or away from the surface of the plasmodium. 



The plasmodium is able to surround and take within itself 

 foreign bodies. These are then enclosed in vacuoles and, as far as 

 possible, digested. The granular plasm seems to be separated from 

 the vacuoles by a pellicle of hyaloplasm, similar to that on the surface 

 of the plasmodium. 



Protoplasmic bodies, or protoplasts, enclosed by cell walls, likewise 

 separate themselves by a similar hyaloplasmic pellicle from the cell 

 walls and sap cavities, and all other vacuoles. The granular plasm is 

 accordingly enclosed on all sides by hyaloplasm, while the cell nucleus, 

 with its centrospheres and chromatophores, always lies embedded in 

 the granular plasm. 



Within the walled protoplasts, the granular protoplasm often 

 exhibits internal flowing movements. Such movements are especially 

 noticeable when, by a wound, such as might result from a cut in 

 preparing a section, a stimulus is given to the protoplasm. In cells 

 in which the protoplasm forms only a peripheral layer, there may 

 frequently be observed a movement in a continuously circling direction; 

 this is known as rotation. If, however, the sap cavity is penetrated 

 by bands or threads of cytoplasm, the motion will generally be of 

 that kind known as circulation, in which case the currents of proto- 

 plasm move in separate courses with different and frequently chang- 

 ing directions. Rotation is the more frequent form of protoplastic 

 movement in the cells of water-plants, while in land plants circulation 

 is generally the rule. 



