A sheet of more than twenty drawings of cats and lions in a wide variety of positions: sleeping, sitting, prowling, playing, fighting and, in one case, frightened, standing with their backs humped and their fur bristling; in the lower half, drawn at an odd angle, is a study of a dragon, its head bent over its shoulder.
This drawing, one of Leonardo da Vinci's most charming, covers the full range of his modes, from the most stylised and 'Leonardoesque', in the coiled dragon, to the most observant and unaffected, in the many studies of domestic cats. The most detailed studies, in the centre right, show the cats sleeping and appear to have been made directly from life, with the subject standing still.
In most of the fights it is difficult to discern which limb belongs to which cat, and in the study in the lower centre he has drawn the two cats enclosed together as a single, almost symmetrical unit, in the manner of a Romanesque sculpture.
Surrounding the studies of domestic cats are seven drawings of a single lioness, mostly crouching or prowling. Leonardo shows in these drawings a clear understanding of their anatomy and proportions. But the unifying interest of the sheet is revealed by Leonardo's short and incomplete note at the bottom:
"Of flexion and extension
That species of animal, of which the lion is the prince because of its flexible spine...".