cratjwub. POMACES. 163 



Order XXVIII. POMACES Loiseleur-Deslongchamps Man. 



PI. Us. i, 211. 



Trees or shrubs with alternate, simple or unequally pinnate 

 leaves, caducous free or nearly free stipules and perfect, regu- 

 lar white or reddish flowers in racemes or corymbosely clus- 

 tered. Calyx-tube urceolate or campanulate, more or less co- 

 herent with the ovary, the usuallv short, free portion lined 

 with an annular or laminar disk, the limb 5-lobed, imbricate 

 in the bud. Petals 5, perigynous. Stamens mostly 20, in- 

 serted on the disk of the calyx. Ovary compound, composed 

 of 2-5 carpels with two collateral ascending ovules in each, 

 becoming a pome; styles as many as the carpels. Seeds usu- 

 ally two in each cell, without albumen. 



* Carpels 1-celled, not divided by a partition from the back. 



1. Crataegus. Fruit drupaceous: ovary 2-5-celled,* becoming 2-5 1- 

 seeded nutlets, either separable or united into one. 



2. Sorbus. Shrubs or small trees with unequally pinnate leaves : fruit 

 a proper pome, with coriaceous undivided 1-seeded cells. 



3. Mains. Trees or shrubs with simple leaves : fruit a proper'pome with 

 chartaceous 2-seeded undivided cells. 



* * Carpels more or less spuriously 2-celled by a partition from the 

 back of each carpel, 



4. Amelanchier. Shrubs or small trees with simple T leaves : fruit a 

 proper pome, 5-carpeled or by abortion 3 or 4-carpeled : carpels coherent, 

 incompletely 2-celled by a partition from the back. 



5. Peraphyllum. Small shrubs with simple leaves : fruit a H proper 

 pome; 2- rarely 3-carpeled; carpels nearly distinct, 2-celled by a par- 

 tition from the back. 



1 CRATAEGUS Tourn. L. Gen. n. 622. 



Thorny shrubs or small trees with simple toothed or lobed 

 leaves, and mostly white, heavy-scented flowers in terminal 

 corymbs. Calyx-tube urceolate, the limb 5-parted. Petals 5, 

 spreading. Stamens 5-20. Carpels 2-5, becoming bony 1- 

 seeded nutlets, contiguous or united : styles distinct. Fruit 

 drupe-like, globose or ovoid, crowned with the calyx-teeth, i [ 



C. Douglasii Lindl. Bot. Reg. 1. 1810. C. rivvlaris Nutt. (?). A stout 

 shrub or small tree, 20-40 feet high : spines stout, 6-12 lines long: leaves 

 elliptical to obovate, usually cuneate at base, irregularly serrate, those of 

 the young shoots often incisely lobed, 1-3 inches long, " somewhat pubes- 

 cent on both sides : inflorescence tomentose ; lobes of the calyx entire, a 

 line long, about half as long as the tube, pubescent inside; petals orbicu- 

 lar, 3-4 lines long : fruit black, 4-5 lines in diameter, often only 3-carpeled; 

 carpels distinct. Along water courses, Brit. Columbia to California, west 

 of the Cascade Mountains. 



C. Columbiana. A much branched shrub cr small tree, 6-15 feet high : 

 spines stout. 1-2 inches long: leaves cuneate-obovate, 1-2 inches long, 

 incisely 5-9-lobed above the middle, acute, serrate, the teeth often viand- 

 tipped, especially below, sparingly pubescent or glabrate, attenuate below 

 to a short petiole : corymbs rather many-flowered, sparingly pubescent or 



