Meinschein et al. : Evidence in Meteorites of Former Life 573 



hydrocarbon mixtures, as is further indicated by the "oil band" absorptions of 

 the benzene eluate in figure 2. 



C23 through C28 aromatics are less abundant in the Murray (table 8) 

 than in the Orgueil. The lower abundance may indicate that the Murray 

 was subjected to a high temperature, more severe environment than the 

 Orgueil and the polyalkyl substituted aromatics may have been partly de- 

 graded in the Murray. Olivine, a high temperature mineral, is a constituent 

 of the Murray meteorite. The simplicity of the aromatic fractions in these 

 meteorites may be explained by assuming that more restricted varieties of 

 organisms existed in the meteorites than are normally found in recent terrestrial 

 sediments. 



/i-Paraffin^'*'^'''^^'*^'*^ and polycycloalkane distributions have been cited as 

 evidence of the biologic origin of some of these compounds.-^ •^^•^^■^^ Most 

 sediments and organisms contain greater abundances of: (1) odd- than even- 

 carbon number //-paraffins in the C21 to C35 range. (2) C24, C27, C28, C29 

 and/or C30 than of other C17 and larger tetra-, penta-, and higher polycyclo- 

 alkanes. Although alterations, which change some organic molecular struc- 

 tures and distributions, decrease the features characterizing biologically 

 derived hydrocarbons, these features apparently persist even in the hydro- 

 carbons from ancient sediments.^'* ■^^•'*^'^'* 



Many of the features noted previously for terrestrial hydrocarbons appear 

 in the mass spectra of the meteoritic hydrocarbons. In the x = -\-2 columns, 

 the 23 and 29 carbon number peaks in tables 4 and 7 and the C25, C27, and 

 C29 peaks in table 5 are larger than the peaks immediately above and below 

 them in the x = -\-2 column. Peaks in the .v = -1-2 are produced by ions 

 that have masses equal to paraffins or heptacycloalkanes. Branched paraffins 

 do not produce "parent ions" to a measurable degree in the mass spec- 

 trometer,^^ '^* and most heptacycloalkanes would contain more than 25 carbon 

 atoms in their ring nuclei. Therefore, the above designated peaks probably 

 contain w-paraffin "parent peaks," and the "peakings" at odd carbon numbers 

 in the C23 to C29 range in these x = -\-2 columns of tables 4, 5, and 7 are similar 

 to "peakings" observed in the mass spectra of saturated hydrocarbons from 

 various ancient terrestrial sediments.^^ 



Other "peakings" and "inflections" (anomalously small differences in sizes 

 between successive peaks in an x column) in tables 4, 5, and 7 are note- 

 worthy. These are: C20 through C30 peaks in the odd numbered x columns of 

 tables 4, 5, and 7 are approximately as large as the even numbered x peaks 

 in this carbon number range. These large odd x peaks and certain of the 

 "peakings" in the odd x columns are indicative of poly alkyl-substituted or 

 branched chain alkanes such as isoprenoids. Saturated hydrocarbons, made 

 by hydrogenating products of the abiotic Fischer-Tropsch synthesis, do not 

 yield as large odd .v peaks as do meteoritic and terrestrial alkanes. A com- 

 parison of abiotic and meteoritic hydrocarbons will be presented in a subsequent 

 publication. 



Because of the chromatographic properties of the fractions and the odd 

 mass numbers of the ions the large peaks at x = — 7, C^ = 15 in tables 4 

 and 5 and at .v = ~5, C^ = 13 and 15 in table 5 are produced apparently 



