-igg ROSACEJC. PruHus. 



21. Aceena. Calyx-lobes valvate, deciduous ; the tube oblong, becoming armed with barbed 



prickles. Petals none. Perennial herbs, with pinnate leaves, and densely spicute-clus- 

 tered tlowers. i i r> i 



22. Poterium. Calyx-lobes inibricate, deciduous, petaloid ; the tube 4-angled, naked. Petuls 



none. Herbs with pinnate leaves, and densely capittite or spicato Uowers. 



Tki1(K V. ROSK.'K. Carpels many, in fruit bony akcnf-.s, enclosed and concealed in the 

 globose or urn-ish;ipcd llu.sliy calyx-tube, which resembles a pome. Petals conspicuous. 

 Stamens numerous. 



23. Rosa. The only genus, lirect shrubs, with pinnate leaves. 



Suborder 111. POIME.K 



Carpels 2 to 5, enc.los(ul in ;uul mo.stly iulnuto to tlio llesliy calyx-tube, in fruit 

 beconiiug a 2 - .sovcrul-cclk'il [)unic. Ovules erect or a.sctuulinjj;, a pair in eaeli eurpel 

 (more numerous in cultivated apples), ascending. Styles often united below. — 

 Trees or shrubs, with stipules free from the petiole or nearly so. 

 » Evergreen : carpels partly free and separating. 



24. Heteromeles. Carpels only 2, tomentoso above, lightly united and in llower nearly 8ui)e- 



rioi, liccoiuing thin and impery, and closely included in the berry-like caly.x. 



♦ ♦ Deciduous-leaved : caipels 2 to 5, united and coalescent with the lleshy or berry-like calyx. 



25. Crateegus. Ovary 2 5-cellcd ; the fruit drupaceous, of 2 to 6 bony 1-seeiied stones, either 



separable or united into one. Branches usually thoniy. 



26. Pyrua. Ovary 2 - 5-celled ; the fruit a proper pome, with }iapcry or cartilaginous and undi- 



vided 2-seeded cells or carpels. 



27. Amelanchier. Ovary 5-celled ; the cells 2-ovuled and 2-seeded, but in fruit each divided 



into two by a partition from the back. Otherwise like Pyrus. 



Anomalous Genus. 



28. Canotia. Calyx free from the sej)ticidally 5-valved exserted capsule. Cells 1 -seeded. Sta- 



mens 5, hypogynous. A leafless shrub, w ith solitary tlowers. 



1. PRUNUS, Tourn. Plum, Cheruy, &c. 



Calyx campanulate or turbinate, 5-cleft, deciduous. Petals 5, spreading. Stamens 

 15 to 25, inserted with the petals. Ovary solitary, free, with 2 pendulous ovules : 

 style terminal. Fruit a more or less lleshy dru[ie, with usually a bony stono con- 

 taining one or rarely two seeds. — Trees or shrubs ; leaves alternate, simple, usually 

 serrulate; ilowers white or rose-culoicd, solitary or fascicled in the axils, or in 

 terminal racemes. 



Species about 80, widely dispersed through the northern hemisphere, but mostly confined to 

 temperate regions. Of the 20 North American species, 14 aie found only in the Atlantic States, 

 from Canada to iMexico. This comprehensive genus now includes several of our most delicious 

 and useful fruits, formerly referred to several genera, such as the Almond, with a somewhat 

 fibrous pitted stone, P. {Amygdalns) communis, — the Peach and Nectarine, with wrinkled stone, 

 P. (Amyc/diihis) Persica,—ihe Apricot, /'. Arme.niaca (Armcninca vu/.ipa-is), — the Gaiden Plum, 

 P. domestica, —the Sloe, P. spinosa,— the Garden Cheriies, P. Cerasus (Ccrasus r uhjans), — also 

 the Cherry- Laurel, P. Lnuru-Cerasus {Lauroccrasus officinalis), &c. Many of the species have 

 medicinal virtues, and the principle or elements of prussic (cyanohydric) acid so abound m sonio 

 species, especially in their kernels and bark, as to make them actually poisonous \shcn eaten 

 freely. Tlie foliage and young branches of some of the Cheriies become poisonous to cattle when 

 wilted. The six Californian species represent nearly as many sections, which have been more or 

 less recently regarded as genera, but the limiting characters prove to be too indefinite. The 

 American species of Plum (belonging to the first section) differ from those of the Old World in 

 having the leaves folded (conduplicate) instead of convolute in the bud, the fruit with little or 

 no bloom, and some of them have very turgid instead of flattened stones, thus connecting this 

 section with the following one. 



