In 1880 M. Pissard, gardener to the Shah of Persia, sent to France a purple-leaved plum which proved to be a form of _Prunus cerasifera_. To this plum Dippel[88] gave the name _Prunus cerasifera atropurpurea_, while horticulturists very generally call it _Prunus pissardi_. A close study of the purple-leaved plum reveals no character in which it differs from the species except in the color of foliage, flowers and fruit; the leaves are purple, as are also the calyx and peduncles of the flowers, while the fruit is a dark wine-red. These are but horticultural characters and do not seem to be of sufficient importance to establish for this plant a botanical variety. This view is strengthened by the fact that Jack[89] reports that seeds from the purple-leaved plum have produced plants which agree in all essential particulars with the species; while Kerr[90] has grown a purple-leaved plum from a variety of _Prunus cerasifera_. Besides this well-known purple-leaved plum nurserymen offer _Prunus pendula_, a weeping form; _Prunus planteriensis_, bearing double white and red flowers; _Prunus acutifolia_, a plum with narrow, willow-like leaves; _Prunus contorta_, characterized by twisted, contorted foliage; _Prunus elegans_, _Prunus gigantea_, and a variety with yellow and another with variegated leaves, etc. All of these are probably horticultural varieties of _Prunus cerasifera_ though some of them cannot be classified with surety. Schneider[91] calls _Prunus dasycarpa_ Ehrhart,[92] the _Prunus armeniaca dasycarpa_ of Borkhausen,[93] a cross between _Prunus cerasifera_ and _Prunus armeniaca_, one of the apricots. =7.= =PRUNUS MONTICOLA= K. Koch =1.= Koch, K. _Ind. Sem. Hort. Berol._ App. 1854. =2.= Schneider _Handb. Laubh._ =1=:632. 1906. Plant shrub-like, slender, upright, scarcely thorny, new wood more or less olive-brown. Buds short, ovate; leaves roundish or cuneiform, base oblong-ovate, point drawn out, main nerves over six on both sides, the serrations coarse and uniform in size, always glabrous. Flowers mostly in twos; borne on long, slender peduncles; calyx usually glabrous; petals white, odor slight; stamens thirty or more. Fruit small, roundish-oblong, red; stone ovoid, pointed at one end, somewhat turgid. _Prunus monticola_ is described by the above authors as a shrub-like plum from Asia Minor and Armenia having, so far as can be learned from European texts, little or no horticultural value. The herbarium specimens seen by the writer indicate that this species is closely related to _Prunus cerasifera_. The description of the species is abbreviated from Schneider. =8.= =PRUNUS TRIFLORA= Roxburgh [Illustration: _PRUNUS TRIFLORA_] =1.= Roxburgh _Hort. Bengal_ 38. 1814. =2.= Ibid. _Fl. Indica_ =2=:501. 1824. =3.= Schneider _Handb. Laubh._ =1=:627. 1892. =4.= Bailey _Cornell Sta. Bul._ 62. 1894. =5.= Waugh _Plum Cult._ 42. 1901.