M O N E R A 



ordinary simple amoebae, and only differ from these to 

 any extent in the absence of a nucleus. The protamocha 

 primitiva seems to be pretty widely distributed; it has 

 been found repeatedly by observers (Gruber, Cienkow- 

 ski, Leidy, etc.) in inland waters. In the zoological 

 demonstrations which I have given at the University of 

 Jena for forty years, and in the course of which the low- 

 ly inhabitants of our fresh water are regularly examined 

 with the microscope, the protamccha primitiva has been 

 found four or five times. It always had the same form, 

 as I described it, moved about by the slow formation of 

 flaps at its surface, multiplied by simple cleavage, and 

 showed no trace of a nucleus in its homogeneous plasma- 

 body even with the most careful application of the 

 modern methods of tinting the nucleus. A larger num- 

 ber of very fine granules (microsoma) that were irregu- 

 larly distributed in the plasm, and were more or less 

 colored by nucleus-reagents, cannot be reckoned as clear 

 equivalents of the nucleus in this or in similar cases; 

 they are probably products of metabolism. The same 

 may be said of the larger marine form of rhizomoneron, 

 which A. Gruber has recently called pclomyxa pallida. 



The large marine form of rhizomoneron to which 

 Huxley gave the name of hathyhius Hccckclii in 1868, 

 and as to the real nature of which many opinions have 

 been expressed, seems, according to the latest investi- 

 gation, not to have the significance ascribed to it. How- 

 ever, the much-discussed question of the bathybius is 

 superfluous as far as our monera theory and the as- 

 sociated hypothesis of archigony (chapter xv.) are con- 

 cerned, since we have now a better knowledge of the 

 much more important monera-forms of the chromacea 

 and bacteria. 



In the case of some of the protists I described in my 

 Monograph on the Monera, it is at present doubtful 

 whether their plasma-body contains a nucleus or not, 



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