A collection of photos showing Enami's variations based on the same stereo negative used to create 'S 763 A group of baby-nurses on a country road'. Included is a comparison to an alternate Stereoview (bottom, photo no.2) from the same photo session, but a slightly different shot which was licensed to Underwood and Underwood. My presumtion is that he would choose the best ones for for his own catalog, and 'lesser' versions for other outlets, but where they would still be unique for their use.
The vertical single-frame 'cabinet card' photo might have been captured by a second and larger-format view camera that was positioned within inches to the left of the Stereoscopic camera used for capturing the smaller stereo images. The larger film format may have been a better choice for providing detailed negatives used in producing mounted non-stereo photographs that were either contact-printed for card views, or enlarged for easy group viewing without the need for a stereopticon or standard projector, or by using any hand-held apparatus like a stereoscope or a table top viewing cabinet.