IRWIN, M. R., and MILLER, W. J. 1961. Interrelationships and evolutionary patterns of cellular antigens in columbidae. Evolution, 15:30-43. JACKSON, A. S. 1941. The mourning dove in Throckmorton County, Texas, Unpubl. manuscript (Abstract). KIEL, W. H., JR., and HARRIS, J. T. 1956. Status of the white-winged dove in Texas. Trans. 21st N. Amer. Wildl. Conf., pp. 376-388. KNAPPEN. P. 1938. Preliminary report on some of the important foods of the mourning dove in the southeastern U. S. Trans. 3rd N. Amer. Wildl. Conf., pp. 776-781. LAKJER, T. 1926. Studien Uber die Trigeminus-versorgte Kaumuskulatur der Sauropsiden. C. A. Reitzel Buchhandlung, Kopenhagen, 154 pp., 26 pls. LEOPOLD, A. S. 1943. Autumn feeding and flocking habits of the mourning dove in southern Missouri. Wilson Bull., 55:151-154. MCGREGOR, S. E., ALCORN, S. M., and OLIN, G. 1962. Pollination and pollinating agents of the saguaro. Ecology, 43:259-267. NICE, M. M. 1922. A study of the nesting of mourning doves. Auk, 39:457-474; 40:37-58. PETERS, J. L. 1934. The classification of some American pigeons. Condor, 36:213-215. 1937. Check-list of birds of the world. Vol. III. Harvard Univ. Press, Cambridge, xiii + 311 pp. ROOTH, J. 1953. On the correlation between the jaw muscles and the structure of the skull in _Columba palumbus_. Kon. Ned. Akad. Wet.; Proc. Sect. Sci., Vol. VI, serie C, pp. 251-264. SALVADORI, T. 1893. Catalogue of birds in the British Museum, 21:xvii + 676 pp., 15 pls. + 17 pp. SHUFELDT, R. W. 1890. The myology of the raven. MacMillan & Co., London, xix + 343 pp., 76 figs. SIMS, R. W. 1955. The morphology of the head of the hawfinch. Bull. Brit. Mus. (Nat. Hist.) Zool., 2:369-393. WETMORE, A. 1920. Observations of the habits of the white-winged dove. Condor, 22:140-146. ZUSI, R. L. 1959. The function of the depressor mandibulae muscle in certain passerine birds. Auk, 76:537-539. _Transmitted June 3, 1963._ * * * * * Transcriber's Notes Italicized text is shown within _underscores_. Bold italicized text is shown within ~_tildes and underscores_~.