Preliminary report on the food of woodpeckers /
by F.E.L. Beal. The tongues of woodpeckers / by F.A. Lucas.
- Washington, D.C. : U.S. Dept. of Agriculture, Division of Ornithology and Mammalogy, 1895.
- 44 p., 3 leaves of plates : ill. ; 23 cm.
- Bulletin / U.S. Department of Agriculture, Division of Ornithology and Mammalogy ; no. 7 .
- Bulletin (United States. Department of Agriculture. Division of Ornitholgy and Mammalogy) ; no. 7. .