ROSACEAK (ROSE KAMILY) 459 



3-10-) fruited ; fruit larger, 8-10 mm. in diameter, elaret-oolored to purplish- 

 black. ^Aronia Britton.) — Similar habitats, centr. Me., southw. aud westw. ; 

 common. 



t/8. P. melanocirpa (Michx.) Willd. Shrub, similar in habit, generally of 

 lower stature ; leaves varying from rather broadly oblong and acuminate to 

 «patulate-obIanceolate and scarcely pointed, glabrous or early glabrate beneath 

 as well as above ; pedicels and calyx also nearly or quite smooth ; fruit very dark 

 purple or essentially black. (^Aronia nigra Britton.) — Moist woods, but also 

 rooky uplands ; common northw. and extending southw. in the Alleghenies at 

 least to N. 0. 



The members of this section occasionally form natural hybrids with those of 

 § 4. These may be recognized usually by their imperfectly pinnate or pinnatifid 

 leaves. 



§ 4. S6RBUS (L.) S. F. Gray. (Mountain Ash.) Leaves odd-pinnate, with 

 rather numerous leaflets; cymes compound; styles distinct; pome berry- 

 like, small. Trees or tall shrubs. Sokbus [Tourn.] L. 



9. P. americana (Marsh.) BC. (American M.) Nearly glabrous or soon 

 becoming so ; leaflets 13-15, lanceolate, taper-pointed, sharply serrate with 

 pointed teeth, bright green ; cymes large and flat ; berries globose, bright red, 

 not larger than peas. (Sorbus Marsh.) — Woods, Lab. to Man., s. to n. and 

 w. N. E., N. Y., the Great L. region, and in the mts. to N. C. ; common. 



10. P. sitchfinsis (Roera.) Piper. Nearly glabrous; leaflets oblong, oval, 

 or lance-ovate, mostly obtuse or abruptly pointed, serrate (often doubly) 

 with more spreading teeth, rather pale beneath, of firmer textm-e than in the 

 preceding ; flowers (earlier) somewhat larger (8-11 mm. broad) ; fruit 8-10 

 mm. in diameter. (P. sambucifoUa Man. ed. 6, not C. & S. ; Sorbus Roem.) — 

 River- banks and damp rooky uplands. Lab. to centr. Me., westw. and north- 

 westw. to the Pacific. 



11. P. Anc0pARiA (L.) Ehrh. (European M., Rowan Tree.) Leaflets 

 narrowly oblong, mostly obtuse, rather pale beneath, always more or less pubes- 

 cent or tomentose at least on the lower surface. {Sorbus L.) — Extensively 

 cultivated for ornament, and now tending to become naturalized. (Introd. 

 from Eu.) 



7. AMELAWCHIER Medic. JriNEBERUT 



Calyx 5-cleft. Petals obovate to oblong, rarely linear. Stamens numerous, 

 short. Styles 5, united below. Ovary 5-celled, each cell 2-ovuled, but with a 

 projection growing from the back of each and forming a false cartilaginous 

 partition, the sweet and edible berry-like pome thus 10-celled, with one seed 

 in each cell (when all ripen). — Small trees or shrubs, with simple leaves, 

 and white racemose flowers. (Name said to be barbaric, the derivation not 

 satisfactorily explained.) 



Petals narrowly oblong, 14^25 mm. in length ; early flowering ; leaves finely 



and sharply serrate X. A. canadensis. 



Petals oblong to obovate, 4-12 mm. in length. 

 Flowers racemed; racemes normally 5-od -flowered ; leaves {at first folded 

 lengtliwise) mostly obtuse, sometimes even cordate at base. 

 Flowering early (mostly 1 Apr.-]5 May, fruit ripe June-July); leaves 



oblong or suborbicular-oblong, finely serrate 2. A. ohlongifolid . 



Flowering later (mostly 15 May-2.5 June, trait ripe Ang.-Sept.); leaves 



suborbicular-oblong, coarsely dentate S. A. spicata. 



Flowers solitary or 2-4 in terminal fascicles ; leaves (flat even in very early 



stages) acutish or subcuneate at base ... ... 4. A.oligocarpa. 



l/ 1. A. canadensis (L.) Medic. (Shad Bush, Service Berry.) Tree or 

 shrub, 3-12 m. high, nearly or soon glabrous; leaves (when young folded 

 lengthvpise and brownish-purple) ovate to ovate-oblong, usually somewhat cor- 

 date at base, pointed, finely and sharply serrate, 4-9 cm. long, 3-6 cm. wide ; 

 bracts and stipules very long-silky-ciliate ; flowers large, in drooping racemes ; 



