The University of Texas Herbarium (TEX) is part of the Billie L. Turner Plant Resources Center, which houses the combined herbaria of TEX and the Lundell Herbarium (LL). The combined PRC collections include over one million specimens from all parts of the world and represent the 13th largest herbarium in the United States. The two herbaria (TEX and LL) are completely integrated and interfiled, although each sheet is marked as to its herbarium and should be cited as such. The University of Texas Herbarium itself, with close to 700,000 specimens, dates to about 1890 and is especially strong in Texas and Mexican specimens. The research interests of faculty, staff, and graduate students have led to very strong representation of Asteraceae, Fabaceae, and Rhamnaceae, among other families, as well as the Chihuahuan Desert region (Mexico and the U.S.) and the mountains and plains of northeastern Mexico. All new specimens received into the Plant Resources Center are now accessioned into TEX.