Initially, taxonomy or the classification of plants was haphazard and inconsistent. In the 17th century there gradually developed a new system, based on the physical similarities between the reproductive features of plants. Thus illustration, which in the herbal tradition had been simply a means of distinguishing one plant from another, now took on the role of analytic tool. It was used to record the detailed physical character of the plant and show the similarity of characteristics.

Ehret presents this subject as a growing plant rather than a cut or uprooted specimen. This mode of representation really belongs to the florilegia tradition, as does the unseasonal butterfly. But his illustration also includes everything necessary for botanical analysis and identification, with flowers shown from several angles and at different stages of opening.