Electronic reproduction. [Place of publication not identified] : HathiTrust Digital Library, 2010.
Master and use copy. Digital master created according to Benchmark for Faithful Digital Reproductions of Monographs and Serials, Version 1. Digital Library Federation, December 2002. http://purl.oclc.org/DLF/benchrepro0212
Vols. 1-7 published by: United States. Dept. of Agriculture, Division of Botany; v. 8-29 by: United States National Museum.
Description based on: Vol. 1; title from PDF title page (viewed Dec. 1, 2010).