The bast layer from the basswood (_Tilia americana_, L.) seems to have been the fiber most commonly and universally used by the Eastern Indians, for it was encountered fifty-two times, in all areas from which specimens were obtained, with the exception of the extreme south. It was utilized for nearly all purposes, from the manufacture of bags to textiles. In the Milwaukee Public Museum is a Menomini bag (4586) made from the _Tilia_ bast, carefully and thoroughly prepared to remove the gums and render the fibers parallel and capable of being spun into good yarn. A Potawatomi bag in this Museum (50.1-7091) is made from the same material. In the Museum of the American Indian, Heye Foundation, is a bag made by the Sauk and Fox (2-4966). In the Peabody Museum of Harvard University is a twilled woven garment (A5479B) made by the protohistoric Indians of Massachusetts. An Iroquois burden strap (AE 2963) in the Rochester Museum of Arts and Sciences is woven of threads from prepared fibers from this tree. In the Ohio State Historical and Archaeological Museum is a prehistoric fabric (957) containing _Tilia_ and three other species of fiber. Hopewell mound and rock-shelter specimens in the same museum show the use of _Tilia_. The above gives a general picture of basswood fiber usage. It was found in an untreated state, merely cut into strips, as well as thoroughly treated and spun into comparatively fine threads. ULMACEAE, Mirbel. (Elm Family) The slippery elm (_Ulmus fulva_, Michx.) was found three times. Once, in a burden strap made by the Iroquois Indians (AMNH 50-6680) in which the fibers had received some preliminary treatment to soften them and remove much of the natural gum. Two other specimens, both rather coarsely woven fabrics from mounds of the Hopewell culture (OSHAM 283 and 125) were in the Ohio State Historical and Archaeological Museum. The American elm (_Ulmus americana_, L.) was encountered only once in an Iroquois burden strap (MAIHF 19-4550). The fiber had received some preliminary treatment and differed decidedly from _Ulmus fulva_ in the shape of the cells, in cross-section, and the residual amount of amorphous material. UMBELLIFERAE