138 THE CASE AGAINST EVOLUTION 



Haeckel, it is true, has attempted to question the status 

 of the cell as the simplest of organisms, by alleging the exist- 

 ence of cytodes (non-nucleated cells) among the bacteria and 

 the blue-green algae. Further study, however, has shown that 

 bacteria and blue-green algae have a distributed nucleus, like 

 that of certain ciliates, such as Dileptus gigas and Trachelo- 

 cerca. In such forms the entire cell body is filled with scat- 

 tered granules of chromatin called chromioles, and this diffuse 

 type of nucleus seems to be the counterpart of the concentrated 

 nuclei found in the generality of cells. At any rate, there is 

 a temporary aggregation of the chromioles at critical stages in 

 the life-cycle (such as cell-division), and these scattered 

 chromatin granules undergo division, although their distribu- 

 tion to the daughter-cells is not as regular as that obtaining 

 in mitosis. All this is strongly suggestive of their nuclear na- 

 ture, and cells with distributed nuclei cannot, therefore, be 

 classified as cytodes. In fact, the polynuclear condition is by 

 no means uncommon. Paramoecium aurelia, for example, has 

 a macronucleus and a micronucleus, and the Uroleptus mohilis 

 has eight macronuclei and from two to four micronuclei. The 

 difference between the polynuclear and diffuse condition seems 

 to be relatively unimportant. In fact, the distributed nucleus 

 differs from the morphological nucleus mainly in the absence of 

 a confining membrane. From the functional standpoint, the two 

 structures are identical. Hence the possession of a nucleus or 

 its equivalent is, to all appearances, a universal characteristic 

 of cells. Haeckel's ''cytodes" have proved to be purely imag- 

 inary entities. The verdict of modern cytologists is that 

 Shultze's definition of the cell must stand, and that the status 

 of the cell as the simplest of organic units capable of inde- 

 pendent existence is established beyond the possibility of 

 prudent doubt. 



With the progressive refinement of microscopic technique, 

 it has become apparent that the law of genetic continuity ap- 

 plies not merely to the cell as a whole and to its major parts, 

 the nucleus and the cell-body, but also to the minor com- 



