Translated from French, it means:
"Figure 34, 3rd part on the right"
This is a reference to a specific illustration in a structured treatise or book. The phrasing strongly supports that this image comes from:
Published posthumously in 1625, this was one of the most influential works on classical horsemanship. The book was illustrated with lavish engravings by Crispin de Passe the Younger, showing detailed training scenes framed like theatrical stages.
Left Shield (argent with three fleurs-de-lis):
This is the traditional symbol of the French monarchy, often used to represent the House of Bourbon.
The fleurs-de-lis are associated with royalty, purity, and divine right.
Right Shield (with a radiating pattern, red and white inside a blue border):
This unusual design corresponds to the Order of the Holy Spirit (Ordre du Saint-Esprit), France’s most prestigious chivalric order, founded by King Henry III in 1578.
The radiating pattern represents the Holy Spirit as a radiant dove or burst.
Crown above:
A royal crown, indicating direct association with a monarch or royal authority.
Collar with the dove medal below:
This is the collar of the Order of the Holy Spirit, confirming the association.
Louis XIII, to whom Pluvinel dedicated his work and whom he tutored in horsemanship.
The imagery combines royal and knightly symbolism to elevate the prestige of the riding school and the book itself.
Such emblems were common in frontispieces or decorative frames in the Instruction du Roy, underscoring the work's connection to the royal court of France.