Botanical pen and ink naturalist study in black ink on white paper of Oleander, featuring delicate lines and precise hatching, with intricate details of the plant's morphology, including the helmet-shaped flowers and deeply lobed leaves, rendered in varying line weights and textures, with an emphasis on accurate representation and observational skill, set against a clean white background that allows the black ink to take prominence, with the overall composition showcasing the unique characteristics of the Oleander plant in a traditional and detailed illustrative style. Show illustration against an outline Art Nouveau letter "O" with Art Nouveau outlines and swirls. Image will be used for a coloring book.