Set of 4 authentic antique naturalist lithographs (circa 1850)

Superb and rare homogeneous set of four authentic naturalist lithographs from the 19th century (19th century litho), sold in their original frames. The back of each frame has the original labels from a prestigious German art gallery: "Die Deutschen Drucke + Kunsthandlung Karl Welter" located in Berlin-Friedenau. The typewritten label from the period precisely indicates the technique and dating: "Alter Steindruck um 1850" (Genuine old stone print / lithograph, circa 1850). Condition: Very good overall aesthetic condition for pieces of this era (approximately 175 years old). The colours of the illustrations have remained fresh and vibrant. The paper has a beautiful natural patina, slightly ambered. The gilded frames show minimal signs of use. Original backs preserved with their Berlin labels. Packed with the utmost care.