Chinese blue-and-white porcelains have for a long time been studied mainly from the general aesthetic and stylistic point of view, and an assesment based on technological considerations has only began to replace this in recent years. This dissertation considers an aspect not yet undertaken in the first approach and is one that attempts an analysis of specialized type concerned as it is primarily with two decorative motifs. These motifs are floral, namely the lotus and peony on the blue-and-white wares of the 14th to the 17th century and the aim is to study their nature with regard to their chronological development. The first section, an introduction, is concerned with the origins of the technique which opened the way to a wide range of decorations; is followed by a brief note on the previous studies on the subject, In the following section the motifs are discussed individually in their various forms, whether stylized or naturalistic, with attention given to the associations with other elements whether floral or animal, the third part, the main catalogue of the material studied is set out in a series of chronologically grouped sections, the objects being analysed and exceptions noted. In the fourth and final section of the dissertation, the chronological discussion is undertaken and the arguments are set out in the same order as in section two in which the motifs are discussed. From this study it is clear that the lotus motif is the most persistent dominant motif over the whole period, while the peony, on the contrary, has a much shorter and less varied life.