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Abundance patterns of the elements C, N, and O are sensitive probes ofstellar nucleosynthesis processes and, in addition, O abundances are animportant input for stellar age determinations. Understanding the nature of theobserved distribution of these elements is key to constraining protogalacticstar formation history. Patterns deduced from low-resolution spectroscopy ofthe CN, CH, NH, and CO molecules for low-mass stars in their core-hydrogen orfirst shell-hydrogen burning phases in the oldest ensembles known, the Galacticglobular star clusters, are reviewed. New results for faint stars in NGC 104(47 Tuc, C0021-723) reveal that the bimodal, anticorrelated pattern of CN andCH strengths found among luminous evolved stars is also present in starsnearing the end of their main-sequence lifetimes. In the absence of knownmechanisms to mix newly synthesized elements from the interior to theobservable surface layers of such unevolved stars, those particularinhomogeneities imply that the original material from which the stars formedsome 15 billion years ago was chemically inhomogeneous in the C and N elements.However, in other clusters, observations of abundance ratios and C isotoperatios suggest that alterations to surface chemical compositions are producedas stars evolve from the main sequence through the red giant branch. Thus, thecurrent observed distributions of C, N, and O among the brightest stars (thosealso observed most often) may not reflect the true distribution from which theprotocluster cloud formed. The picture which is emerging of the C, N and Oabundance patterns within globular clusters may be one whichComment: 12 pages in uuencoded compressed postscript (including figures), to  appear in the Canadian Journal of Physics (Special Issue in Honor of G.  Herzberg

Light element abundance inhomogeneities in globular clusters: probing star formation and evolution in the early Milky Way