626 ROSACEAE 
25. ROSA [Tourn.] L. Prickly ipie sometimes vine-like. Leaf ad 
hium 
en ined pinnate. Flowers solitary or orymbs, often showy. Hypan 
urceolat fare ore or less AMEN Petals 5, broad. Stamens many. 
Achenes mes nelosed in the pulpy hypanthium. Many species, nur more 
than 100, wi widely nnd in the Northern Hemisphere.—Spr.-sum.—Ros 
—The following treatment is based on that of Per Axel Rydberg in ed 
American Flora. 
Styles much exserted,.united, about equalling the stamens: stipules di sepals 
reflexed. I. SYNSTYLAE. 
Styles not exserted or only slightly so; stigmas s aggregated into 
a head which closes the mouth of the hypanthium. 
Stipules almost eee from the petiole: naturalized climbing 
or trailing 
Leaflets 3-5 : brin ies glabrous: stipules small, entire. II. LAEVIGATAE. 
Leaflets 5-9 : branches eee stipules pectinate, III. BRACTEATAE. 
Stipules noe ate to the petiole: erect, or rarely climbing 
plants 
 Achenes "borne both in the inner walls and in the bot- 
tom of the hypanthium which is elabrous or glandu- 
Ene only at the base: prickles rarely infra- 
sti IV. CANINAE. 
Achenes. Dorie in the bottom of the glandular-hispid 
: hypanthium: vans Ded. Den borne on the stem, 
the shoots usually bri V. CAROLINAE. 
a SYNSTYLAE 
Stipules pectinate. 1. R. multiflora. 
Stipules entire or denticulate. 
Leaves of the flowering branches with 5-7 leaflets : petals 
ite. 2. R. moschata. 
Leaves of the flo owering branches with 3, or rarely 5, leaf- 
lets : petals pink. 
Blades of the Taa glabrous or slightly pubescent on 
the veins beneath, dark-green and shining above. 3. R. setigera. 
Blades ds the leaflets velutinous beneath, rather dull 
abov 4, R. rubifolia. 
II. LAEVIGATAE 
Eo narrowed at the apex: hypanthium and fruit 
bris 5. R. laevigata. 
III. BRACTEATA 
Leaflet-blades rounded at the apex: hypanthium i fruit pu- 
berulent. 6. R. bracteata. 
IV. CANINAE 
Leaflets glandular-pruinose beneath: blades manifestly doubly 
serrate with gland-tipped teeth. 
Stem with straight or eh straight prickles. T. R. tomentosa. 
Stem with strongly curved prickles 
"Blades of the leaflets “suborbicular to broadly oval, 
mostly rounded at the x: mature hypanthium obo- 
void or broadly ellipsoid, eae contracted at the 
apex: sepals pem denas or somewhat per- 
sistent: styles pubes 8. R. rubiginosa. 
Blades of the leaflets pesos acute or short-acuminate : 
mature hypanthium narrowly ellipsoid, ee at 
bot d ends: sepals rather early deciduous: styles gla- 
brous or nearly so. 9. R. micrantha. 
Leaflets Bob aa Bence tis blades singly serrate or some- 
what doubly serrate. 10. R. canina. 
V. CAROLINAE 
Infrastipular prickles decidedly curved. 
Blades of the leaflets finely serrulate, elliptic or oblanceo- 
late: prickles short and stout. : 
M is: uu 7: flowers usually corymbose on erect 
bran mature hypanthium about 12 mm. thick. 11. R. palustris. 
get d on spreading branches: mature hypanthium 8- 
d i 12. R. floridana. 
Blades of "the aflets coarsely serraté, oval or obovate. 13. R. virginiana. 
Infrastipular prickles straight or nearly so. 
