amber. In the New World there are no fewer resins, 
but, since they have been studied by biologists rather 
than mineralogists, few have been given names. 
Even now, the only reasonably inclusive listing of fossil 
resin occurrences, restricted largely to the named varie- 
ties, are to be found in the back pages of standard works 
on mineralogy or mineral chemistry, such as those of 
Dana (1895), Hintze (1983) or Doelter and Leitmeier 
(1930). Their description by standard mineralogical 
procedures, which are ill suited to complex, largely 
non-crystalline, organic materials, does not provide an 
acceptable basis for classification. It is indeed no ex- 
aggeration to say that fossil resins have not yet been 
ordered into a classification system. Mineralogical com- 
pendia make broad distinctions between ‘‘families’’ con- 
taining or lacking succinic acid, sulfur or nitrogen, but 
these superficial criteria do not reflect any meaningful 
relationship in establishing a natural classification system. 
Paclt (1953) has suggested asystem ordered by geologic 
age and botanical origin. ‘he former criteria, unfortu- 
nately, have had to be based on meager and scattered 
published evidence. Most often, the botanical origin, 
which is based on associated fossil plant remains, is in- 
dicated without supporting evidence because of lack of 
available data in the literature. Botanical source unques- 
tionably is the most significant basis for classification of 
fossil resins, since they are plant products the chemical 
composition of which is genetically controlled (Mirov, 
1961; 1967). Also study of the botanical source of fossil 
resin through geologic time provides an opportunity to 
observe evidence of biochemical evolution within the 
populations that produce the resin. Resins from some 
populations appear to have a relatively stable compo- 
sition through millions of years, whereas others have 
changed considerably. The determination of the origin 
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