A plum with pubescent leaves belonging to the Americana series known locally as the Big Tree plum, occurs from western Tennessee, south-westward through the extreme southern portion of Missouri, through Arkansas, southern Oklahoma, extending westward in central Texas, at least, as far as the Colorado River and reaching its southwestern limit in northern Mexico. From specimens of this plum in several herbaria and from studies made of it in the field by W. F. Wight of the United States Department of Agriculture, it would seem that this plum is a distinct species, its chief distinguishing character being the great size attained by the tree. So far as it is known the Big Tree has no cultivated forms unless it be Bilona, supposed to be a hybrid between this species and _Prunus triflora_, now growing on the grounds of F. T. Ramsey, Austin, Texas. =11. PRUNUS HORTULANA= Bailey[116] [Illustration: _PRUNUS HORTULANA_] =1.= Bailey _Gar. and For._ =5=:90. 1892. =2.= Sargent _Sil. N. Am._ =4=:23, Pl. 151. 1892. =3.= Waugh _Vt. Sta. An. Rpt._ =10=:99-105. 1897. =4.= Mohr _Torrey Bot. Club Bul._ =26=:118. 1899. =5.= Bailey _Cyc. Am. Hort._ 1450, fig. 1901. =6.= Mohr _Cont. U. S. Nat. Herb._ =6=:551. 1901. _P. americana_, var.? 7. Patterson _List Pl. Oquawka_ 5. 1874. Tree attaining a height of thirty feet or more, vigorous in growth; trunk sometimes a foot in diameter; trunk and branches rough and shaggy becoming furrowed in age; bark gray-brown, thick and containing deposits of red cork cells which show as bright red blotches or as thick layers when the bark is sectioned, these deposits, especially in quantity, characterizing the species; branches very spreading and open, twiggy, slender, thorny; branchlets light green at first, becoming reddish-brown, glabrous and glossy; lenticels few, large, very coarse, raised, characteristic of the species. Winter-buds plump, very small, obtuse, appressed; leaves one and three-quarters inches wide to five inches in length, long-oval with a tapering, pointed, acuminate apex, peach-like, base abrupt, texture thin, becoming leathery, margins serrate, almost crenate, sometimes in a double series, glandular; upper surface smooth, glossy, glabrous; lower surface light green, almost glabrous except on ribs and veins which are very pubescent, with characteristic orange color, midrib grooved above, rounded below, very prominent; petioles slender, an inch in length, pubescent on the upper side, tinged with red; glands two to eight, small, globose, mostly on the petioles.