Papp: Fossil Protobionta 463 



is a single cell whose plasma is protected by a resistant cell wall. The stronger 

 the wall, the more likely it is to have perforations (pores or marks) which allow 

 the plasma to come in contact with the surrounding environment. Only the 

 most primitive organisms reproduce by simple cell division. All higher forms 

 of life depend upon sporomorpha to survive hostile periods and to reproduce. 

 According to G. Erdtmann, sporomorpha in the broadest sense are spores whose 

 position in the system in unknown. Although they do not always exhibit 

 trilete markings, their three-sided symmetry may indicate that reduction 

 division has taken place. One of the criteria of survival is that during the 

 Dauerstadium substances needed to maintain life be reduced to a minimum. 



The basic importance of reduction division (meiosis) to genetic propagation 

 has already been mentioned. It should also be noted that tetrahedral meiotic 

 division results in spores with three-sided symmetry. However, three-sided 

 symmetry is the rule with the widespread trilete spores and the exception with 

 protobionta and, in fact, with the total animal and plant kingdom. From the 

 above definition of sporomorpha, it is reasonable to apply this term to the 

 organized elements of extraterrestrial life having three-sided symmetry, i.e., 

 the triporate or trilete forms. This does not specify their position in the sys- 

 tem, nor does it suggest that an organism similar to an organized element is 

 equivalent to it. The possibility that organized elements with three-sided 

 symmetry result from reduction division may not be excluded in the case of 

 extraterrestrial life. The function of such division is also a possibility in an 

 extraterrestrial environment . 



Residues of extraterrestrial organisms could not be preserved at all except 

 for a process which may be called fossilization. The following rule holds in all 

 circumstances: the more residues, the more favorable were the conditions of 

 fossilization. This requirement is undoubtedly best fulfilled on earth in the 

 aquatic medium which offers conditions for suitable embedding. 



The organized elements w'ith resistant exines or organic material must have 

 depended on the functions of protein molecules. In this event the extrater- 

 restrial temperature range of the organized elements' environment would have 

 to be similar to that on the earth. 



A cknowledgments 



I wish to thank Dr. W. Klaus, Dr. A. Freisinger, and Dr. K. Turnovsky for 

 many stimulating discussions on this subject. 



