Sweetbay (Magnolia virginiana)
"Sweetbay is found in swampy woods or deep swamps where it is usually a shrub, although sometimes attaining the size of a tree. The leathery leaves are silvery beneath, and their upper surface is a rich dark green. The solitary flowers are borne at the tips of the branches, where the creamy petals contrast pleasingly with the deeply colored foliage. Their delicious and pervasive odor is their greatest attraction. […] This striking member of the Magnolia Family is found around the Gulf of Mexico from Florida to Texas and Arkansas, and northward along the Atlantic coastal plain to Pennsylvania and Massachusetts."
This illustration and the description are from "North American wild flowers" by Mary Vaux Walcott. (Published by The Smithsonian Institution, 1925)