The style of embedding illustrations within a text block or floating on a page of a book surrounded by text or other design items is not a characteristic of the illustration itself.
The illustrations themselves simply have no background. The images “float” on a featureless background. You might say they are “in limbo.” Often, normal square framed illustrations are “shopped” to drop-out everything but the desired detail. The irregular outline or profile of the illustrations are then embedded which is a characteristic of the typographic style of the document.
The text is loosely or tightly “tucked” or “tucked-in” around the illustration profile or object shape.
This is referred to as Wrapping Text.
Your sample shows text that is arranged to flow around the floating images and other objects. It is also referred to as Text Runaround. Sometimes layout software uses the term “Text Effects.”