266 THE MICROSCOPE. 



under the name of the Proteus (Amoeba diffluens, fig. 163,) 

 which, from the continual changes of shape it presents, 



Fig. 163. Amoeba diffluens, or Proteus. 



is honoured with the name of a fabled god, who could 

 be either animal, vegetable, or elemental in his nature. 

 This curious animal presents us with the essential cha- 

 racters of all the class Rkizopoda in their simplest form. 

 It appears to be of an exceedingly voracious disposition, 

 seizing upon any minute aquatic animals or plants that 

 may come in its way, and appropriating them to the 

 nutrition of its own gelatinous body. The mode in which 

 this tender and apparently helpless creature effects this 

 object is very remarkable. The gelatinous matter of which 

 it is composed is capable, as we have seen, of extension in 

 every direction; accordingly, when the Amoeba meets with 

 anything that it regards as suitable for its support, the 

 substance of the creature, as it were, grows round the 

 object until it is completely enclosed within its body. 

 The substances swallowed (if such a term be admissible) 

 by this hungry mass of jelly are often so large, that the 

 creature itself only seems to form a sort of gelatinous coat 

 enclosing its prey. 



Professor Ecker believes in an exact similarity of con- 

 tractile substance between that of the lower animal forms, 

 such as the Rhizopoda, and that observed in the Hydra. 

 He says : " The properties of this substance, in its simplest 

 form, are seen in the Amoeba, the body of which, as is 

 known, consists of a perfectly transparent albumen-like 

 homogeneous substance, in which nothing but a few 

 granules are imbedded, and which presents no trace of 

 further organisation. This substance is in the highest 

 degree extensible and contractile; and from the main mass 



