Previous work has demonstrated that catecholamine-containing cells differentiate preferentially from populations of quail trunk neural crest cells isolated by cell sorting using the HNK-1 antibody (Maxwell, Forbes, and Christie, 1988). In the present work, we examine several additional features of the differentiation of these sorted cell populations. As one part of this study, the development of subpopulations of the HNK-(1+)-sorted neural crest cells has been investigated. Twice as many catecholamine-positive and total cells developed from the brightest third of the HNK-1+ cells compared to the remaining HNK-1+ cells, but the proportion of catecholamine-containing cells was similar in both populations. When either of these HNK-1+ subpopulations were grown together with HNK-1- cells, no reduction in the number of adrenergic cells was observed. These results indicate that subpopulations of HNK-1+ cells are qualitatively similar and that their adrenergic development is not affected by HNK-1- cells. In the second part of this study, we investigate the specificity of differentiation of HNK-(1+)- and HNK-(1-)-sorted cells by examining several additional phenotypic markers of development. We found that tyrosine hydroxylase and somatostatin immunoreactive cells developed from the HNK-(1+)-sorted population, while few, if any, cells bearing these phenotypic markers appeared in the HNK-(1-)-sorted population. In marked contrast, substantial numbers of cells immunoreactive for A2B5, E/C8, and NF-160 differentiated from both the HNK-(1+)- and the HNK-(1-)-sorted cell populations. The A2B5, E/C8, and NF-160 immunoreactive cells exhibited a variety of morphologies ranging from nonneuronal to neuronal in both sorted populations. Taken together, these results indicate that the presence of the HNK-1 antigen(s) on the trunk neural crest cell surface at 2 days in vitro is rather tightly correlated with the differentiation of adrenergic and some peptidergic cells, but much less so with other classes of neural cells including A2B5, E/C8, and NF-160 immunoreactive cells. Thus, these findings support the view that cell surface differences are correlated with and may contribute to the generation of the phenotypic diversity of neural crest cell derivatives.