Observations on surface ornamentation in fossil Ostracoda

Abstract. It has recently been demonstrated (Okada, 1982) that some reticulate Ostracoda develop ornamentation by a process which reflects the arrangement of underlying epidermal cells. Pitting and secondary reticulation are also characteristic of many such forms, either during ontogeny or phylogeny, and as these features are of lesser dimensions than epidermal cells, a process at variance with that described by Okada must be responsible for their production. Outlined below is evidence from fossil Ostracoda supporting the hypothesis that actual valve resorption may occur during ontogeny to produce these second order features.