As indicated by the caption, this image shows a nude sculpture of Peter Brant's wife Stephanie Seymour that Brant commissioned.
The caption accompanying this photograph reads as follows:
Famous for helping clients to disavow their youthful folly, had Duveen been able to banish Mackay's Gerome? All things considered, as focal point of the conservatory, it must have been disconcerting for many much as the portrait of his wife, Stephanie Seymour, that Peter Brant commissioned. More than anything, one wonders, what did Katherine think?
See Harbor Hill, Clarence Hungerford Mackay's Mansion.