40 VIEWS OF THE MICROSCOPIC WORLD. 



this is not the case ; on the contrary, the color appears in distinct round spots, 

 from having accumulated in globular cells, and, by careful investigation, the tube 

 connecting these cells may be detected." 



THE TREE-ANIMALCULES. The Bell-shaped Infusoria, which have just been 

 described, are each attached to a common base, by a separate stalk ; but in the 

 kind we are now considering the entire cluster springs from a single trunk, 

 which, dividing and subdividing into numerous branches, puts forth its trumpet- 

 shaped living blossoms, at the extremity of every bough. This mode of union 

 is the result of imperfect self-division a single animalcule first separating into 

 two, that are united by a forked stem, and these again into four, which still 

 remain connected ; thus the division proceeds, until the limit of development is 

 attained, and a graceful, branching cluster rises from a common stalk. The spon- 

 taneous separation of the individual creatures is effected in the manner already 

 detailed, and, as in the case of their kindred species, the Tree-animalcule, upon 

 arriving at maturity, breaks away from the parent stock, and the single living 

 cup, floating for awhile, at length becomes stationary, and a new generation of 

 arborescent forms are produced, by their repeated self-division. These Infusoria 

 have also been observed to multiply by the growth of buds. 



The Tree-animalcule is shown in figures 51 and 52. In the latter engraving 

 the beautitul group is seen fully developed, with the trumpet-shaped animals 

 clustering on every branch ; their circles of cilia expanded to the utmost, and 

 Fi? 51 the position of their stomach-cells clearly indicated by the 



round spaces within their bodies. A muscle is distinctly 

 seen rising from the root, traversing the trunk, and extend- 

 ing its minute ramifications to every member of the 

 group. Not only is each individual endowed with the 

 power of coiling and uncoiling its own stalk, by the aid 

 of this muscle, independently of the action of its fellows, 

 as shown in the cut, but the whole group can suddenly con- 

 tract its dimensions, the main trunk folding closely together 

 in spiral wreaths, and the spreading tree shrinking into a 

 globular mass, while each animalcule assumes a spherical 

 shape, and its crown of cilia occupies a narrower circle. 

 This attitude of the group is exhibited in figure 51. The 

 natural size of a single animalcule ranges from one-four 

 Hundred and thirtieth of an inch to one- jive hundred and seventieth. 



The living forms that constitute the Infusorial world, bear, for the most part, 

 little or no resemblance to those that are visible to the unaided eye ; but in the 

 beautiful groups we have just considered it is otherwise ; for, in their curious 

 figures and organization, that type of animal existence is recognised, which adorns 

 the ocean with living flowers, and peoples its azure depths with a thousand 

 arborescent forms ; where a sensitive life is enshrined in each bud, and which, 

 developed in its countless generations, spreads through the waters, a mazy grove. 



