Although these buildings are based on the mid-1900s romantic ornamentation theme, they strongly represent the Gothic theme and even states that in the book's caption. I can immediately see this by the slenderness of the buildings, the triangular arcs and the elegant detail following them. The book states the style of the building as "Romantic Gothic Style". The picture above is most like what the gothic architecture was at it's time mainly because of the colour and the picture next to it is a much more modern transformation of the building.

The picture above is a Gothic mansion, it represents this theme through it's Gothic towers, arches, tallness and the great detail which adds a delicate side to it.
The picture on the right is called the "Harkness Tower" which follows the Gothic Revival style. It also follows the style of the slenderness especially as it's a tower.

This building on the right is a "Gothic Prototype" made in 1937. Likewise to one above, it is slender and cathedral like, however this one includes a lot more depth of detail. The colour is also within the Medieval sort of colour scheme as it hasn't been modernized in any way.



Reference: "American Architecture- colonial styles to the present day, Robin Langley Sommer with photographs by Balthazar Korab"
 (scanned in research from a book)