*POMACEAE (APPLE FAMILY) 265 



high, armed with stout, straight or recurved spines, the branches sometimes 

 unarmed, and young shoots sometimes prickly: stipules glandular-ciliate; 

 leaflets 5 or 7 (very rarely 9), broadly elliptic to ovate or oblong or lanceolate, 

 usually rounded at base, obtuse or acute (the terminal 2-5 cm. long), resin- 

 ous beneath (as well as the rachis and stipules) and the teeth more or less 

 glandular-serrulate, smoother above, sometimes nearly or quite glabrous (and 

 teeth entire), or the pubescence not resinous; rachis more or less prickly or 

 hispid: flowers 5-7 cm. broad, solitary (rarely 2 or 3); pedicel and receptacle 

 very rarely hispid; sepals naked or very rarely hispid: fruit globose, not con- 

 tracted above into a neck, 12 mm. broad (Watson, 1. c.). (R. melina Greene, 

 Pitt. 4: 10. 1899; R. oreophila Rydb. Bull. Torr. Bot. Club 31: 561. 1904; 

 R. grosseserrata E. Nels. Bot. Gaz. 30: 119. 1900.) From Colorado to the 

 far northwest. 



6. Rosa gymnocarpa Nutt. T. & G. Fl. N. A. 1: 461. 1840. Stem slen- 

 der and weak, 1-3 m. high, with straight slender spines: stipules narrow, 

 glandular-ciliate; leaflets 5-9, glabrous, doubly glandular-toothed, sessile or 

 nearly so: flowers solitary or few: sepals 6-12 mm. long, entire, spreading after 

 flowering and deciduous (with the distinct styles) from the very contracted top 

 of the naked, oblong-ovate to globose fruit. -Scarcely within our range; west- 

 ern Montana and Idaho to the Pacific States. 



7. Rosa stellata Wooton, Bull. Torr. Bot. Club 25: 152. 1898. Stems 

 4-6 dm. high, with numerous straight or slightly curved yellowish spines; 

 young stems closely covered with stellate trichomes which may be scale-like 

 or have a central gland-bearing axis, or this axis may be a well-developed 

 spine: leaves small, 3-5-f oliolate ; leaflets triangular-cuneate, with rounded 

 acute teeth; stipules spreading, silky-pubescent, not glandular: flowers soli- 

 tary, 4-7 cm. broad: calyx-lobes enlarged, glandular on the margin, generally 

 laciniately lobed: fruit spiny, reddish-brown. New Mexico and probably 

 reaching southern Colorado. 



8. Rosa MacDougalii Holz. Bot. Gaz. 21: 36. 1896. Resembling R. 

 Nutkana: stems with few epidermal spines, or frequently none, the infrastip- 

 ular spines wanting: flowers solitary at the ends of short leafy branches: re- 

 ceptacle and calyx conspicuously glandular and hispid: fruits densely spiny. 

 (R. Underwoodii Rydb. Bull. Torr. Bot. Club 31: 560. 1904.) Colorado to 

 Idaho. 



55. POMACEAE L. APPLE FAMILY 



Trees or shrubs with alternate, pinnate, simple or compound leaves; the 

 stipules free from the petiole and early deciduous. Flowers regular, solitary 

 or in cymes or racemes. Calyx 5-lobed or toothed, adnate to the ovary. 

 Stamens usually many, distinct. Ovary 1-5-celled, of as many carpels, more 

 or less united; the ovules one or more in each cell. Fruit a fleshy pome, 

 formed by the calyx-tube becoming thickened-fleshy and inclosing the 1-5 

 bony, papery, or leathery carpels. Rosaceae in part. 



Leaves simple. 



Flowers many, in racemes; pome berry-like . . . . . 1. Amelanchier. 



Flowers several, in short corymbs; seeds bony 2. Crataegus. 



Flowers solitary or 2-3 in sessile umbel; seeds cartilaginous . . 3. Peraphyllum. 



Leaves pinnately compound 4. Sorbus. 



1. AMELANCHIER Medic. SERVICE-BERRY 



Shrubs with alternate, simple, serrate leaves and white flowers in racemes; 

 not thorny. Calyx-tube adnate to the ovary, its five lobes persistent and 

 reflexed. Petals 5, inserted with the numerous stamens on throat of the 

 calyx. Styles connate, 2-5; cells of the f ovary as many as the styles, becom- 

 ing in the berry twice as many, with 1 cartilaginous seed in each cell. 



