In fruit-growing, the Miner-like plums behave in general much like the Americana plums. In some respects the fruits are an improvement upon those of the Americana varieties. For example the skin in the Miner-like varieties is usually less tough; is brighter in color and the flavor, in most cases, is a little better. These plums seem to be nearly or quite as hardy as the Americanas and are adapted to quite as wide a range of soils. Presumably they have the same value as stocks, though they seem not to have been tried for this purpose and they should have equal value at least in plant-breeding. The trees of the Miner-like plums are rather more amenable to domestication than those of _Prunus americana_ having as orchard plants straighter trunks, more symmetrical and less unkempt tops and making larger trees. The fruits ripen so late as to make the varieties of this group especially valuable in prolonging the season for plums in regions where native varieties are grown exclusively. About twenty varieties of this sub-species are under cultivation. =12.= =PRUNUS NIGRA= Aiton [Illustration: _PRUNUS NIGRA_] =1.= Aiton _Hort. Kew._ =2=:165. 1789. =2.= Sims _Bot. Mag._ 1117. 1808. =3.= Pursh _Fl. Am. Sept._ =1=:331. 1814. =4.= Torrey _Fl. U. S._ =1=:469. 1824. =5.= Sargent _Silva N. Am._ =4=:15, Pl. 149. 1892. =6.= Small _Torrey Bot. Club Bul._ =21=:301. 1894. _Cerasus nigra._ =7.= Loiseleur _Nouveau Duhamel_ =5=:32. 1812. _P. americana_ (in part). =8.= Torrey and Gray _Fl. N. Am_. =1=:407. 1840. 9. Torrey _Fl. N. Y._ =1=:194. 1843. =10.= Emerson _Trees of Mass._ Ed. 2, =2=:511. 1846. =11.= Nuttall _Silva_ =2=:19. 1852. =12.= Sargent _10th Cen. U. S_. =9=:65. 1883. =13.= Watson and Coulter _Gray’s Man._ Ed. =6=:151. 1889. =14.= Gray _For. Trees N. A._ 46, Pl. 1891. _P. americana nigra._ =15.= Waugh _Vt. Sta. Bul._ =53=:60, fig. 1896. =16.= Ibid. _Vt. Sta. An. Rpt._ =10=:102. 1897. =17.= Bailey _Cyc. Am. Hort._ 1449. 1901. _P. mollis._ =18.= Torrey _Fl. U. S._ =1=:470. 1824. Tree small, seldom exceeding twenty feet in height; trunk attaining six or eight inches in diameter, bearing the head at three to five feet from the ground; bark thin, one-quarter inch thick, from dark red to a light gray-brown, rough, but not shaggy, surface covered with thick scales; branches upright, stout, rigid, forming a compact rather narrow head, armed with stout, spiny spurs; branchlets more or less zigzag, glabrous or tomentose, green, later becoming reddish-brown; lenticels few or many, pale, slightly raised.