LIVING MATTER IN "PROTOPLASM" 23 



a lump. Some of the lumps remain in the shape described 5 

 most of them, however, after a few minutes, gradually resume 

 the granular condition with increase of their circumference ; at 

 the same time they become globular and again nucleated. Such 

 an amoeba remains motionless. 



In still older infusions, amoebas make their appearance which 

 are characterized by large size, slowness of locomotion, and the 

 property of pushing out radiating offshoots. Such amoebae 

 are especially sensitive to the action of distilled water. By 

 placing a drop of distilled water at one edge of the covering- 

 glass, and draining off the infusion water from the opposite 

 edge, the following observation was made: Instead of long, 

 radiating offshoots, broad and short flaps were protruded, the 

 long offshoots already present were gradually retracted, and loco- 

 motion ceased. Slowly the amoeba assumed a blunt, polygonal 

 shape. In its body vacuoles appeared, at first small, gradually 

 larger ; the nucleus became indistinct, and afterward completely 

 faded away. Some of the granules, with jerking movement, 

 united into larger groups, while others were seen to float in larger 

 meshes. The more the number of such free granules increased, 

 the more the amoeba approached the globular shape. At the 

 same time, many small vacuoles coalesced into a single large one, 

 and a globular protrusion at the periphery of the body resulted. 

 Both the protrusion and the body of the amoeba were seen to be 

 inclosed by a continuous shining layer. Within the vacuole, 

 small granules moved about. In the meantime the jerking 

 motion of the grouped granules had ceased, and the number of 

 the floating ones became considerably augmented. 



This description of the appearances after addition of water is 

 taken from one amoeba ; but all amoebae of the radiating variety, 

 under similar circumstances, exhibited the same features. 



Blood-corpuscles of the Craw-fish (Astacus). In a drop of 

 blood, transferred from a broken limb of a living fresh craw-fish 

 upon a slide, and covered with a covering-glass oiled on its edges, 

 we recognize the blood-corpuscles with moderate powers of the 

 microscope. E. Haeckel * found these corpuscles to be amoeboid. 

 Two kinds of such corpuscles are noticeable, viz. : pale and finely 

 granular ones with nuclei, which are either large and pale or small 

 and coarsely granular ; and, second, others having only coarse, 

 yellowish, very shining granules. The granules of the latter 

 kind, as a rule, encircle light spaces containing scanty granules. 



*Ueber die Gewebe des Flusskrebses. Miiller's Archiv. 1857. 



