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VIEW6 OF THE MICROSCOPIC WORLD. 



own independent and proper instinct ? This it undoubtedly enjoys, when sepa- 

 rated from the rest; and if it is endued with this when in union with the others, 

 the enigma becomes still more perplexing ; for the question then presented is 

 the following : What means of intelligent communication exist between the 

 sixteen distinct monads of a cluster, by which they have the power of acting 

 harmoniously, so as to produce, at intervals, several common motions ; one of 

 which motions they do not possess when separate from the group ? Speculations 

 like these will naturally arise, when we contemplate such curious and unique 

 modes of existence ; but a still more complex union of individual life is revealed 

 in the next species of Infusoria to be described. 



THE REVOLVING GLOBE-ANIMALCULE. About one hundred and fifty years 

 ago, Leuwenhoeck discovered in water, an animated hollow globe, studded with 

 green specks, which advanced through the fluid with a rolling motion. It was 

 at first supposed that the globe was a single animal, but the superior microscopes 

 of the present day have shown that this is not the case. The little green specks 

 that gem the surface are the true animals ; each being a perfect monad, fur- 

 nished with two cilia, and possessing a bright red eye. They are all connected 

 together, and every individual is attached to those immediately adjacent by 

 delicate fibres, varying, in number, from three to six. The thousands thus 

 imbedded throughout the entire surface of the transparent spherical shell, form 

 the hollow globe, and bear to it the same relation as the monads of the breast- 

 plate cluster to their pellucid case. The whole globe bristles with the cilia of 

 the individual monads ; and by the united action of these slender organs, rolls 

 through the water with the same part always foremost : "when the fluid is colored 

 the current and eddies produced by the cilia are clearly detected. The motion 

 of the cilia is regarded by Mantell as involuntary, like that of the chest in the 

 act of respiration ; and he considers that it subserves a similar purpose, by 



bringing the globe, with its countless pop- 

 ulation, into contact with fresh portions 

 of water, from which a constant supply of pure 

 air is derived, without which these living atoms 

 must inevitably perish. This change of place 

 is also necessary for the support of the nu- 

 merous groups, which range continually in their 

 rolling globe, through new regions of space, 

 abounding with appropriate food. In figure 

 14, the revolving globe is faithfully delineated. 

 The minute dots with which it is covered are 

 the monads that compose it, and the inter- 

 lacing net-work are the filaments which con- 

 nect them with each other. The direction of 

 the globe in its progress is indicated by the 

 arrows, and the cilia that propel it are dis- 



Fig. 14. 



