Female Becker's white (Pontia beckerii) - a species of butterfly - specimen, pressed inside of an almost flat, rectangular, plastic container. There is a raised "bubble" in the center of the plastic that houses the body of the specimen.

Original label identifies specimen as “[Female] Pieris Beckeri Pseudochloridice” - seemingly referring to a subspecies no longer considered valid - and suggests that it was collected at Monument Canyon, Colorado.