500 NORTH AMERICAN FLORA [VOLUME 22 
DISTRIBUTION: Maine to Florida, Texas, Kansas, and Wisconsin. 
ILLUSTRATIONS: Dill. Hort. Elth. pl. 245, f. 316; Redouté, Roses 2: pl. opp. 73 (form); Loud. 
Arb. 2: f. 479; Miller & Whiting, Wild Fl. 151; Britt. & Brown, Ill. Fi. f. 1971; ed. 2. f. 2314; Willm. 
Gen. Rosa pl. opp. 201; Meehan, Nat. FI. 2: pl. 9 (as R. lucida); Stand. Cycl. Hort. f. 3444; Peter- 
son, Wild Fruits 60, f.; G. T. Stevens, Ill. Guide pl. 70. f. 5; Andr. Roses pl. 103; pl. 104, 105 (double). 
Rosa acicularioides X carolina. See under R. acicularioides. 
Rosa acicularis < carolina. ‘This has the low habit and bristly hypanthium of R. carolina but 
the pubescent and rugose leaves of R. acicularis. The hypanthium is pear-shaped but much smaller 
than in the latter species; the sepals are erect and persistent. Little Sturgeon, Wisconsin, 1890, 
Schuette (Gray Herb.). 
Rosa carolina X palustris. See under R. palustris. 
Rosa carolina < virginiana. See under R. virginiana. 
26. Rosa serrulata Raf. Ann. Gén. Sci. Phys. 5: 218. 1820. 
Rosa parviflora glandulosa Crépin, Bull. Soc. Bot. Belg. 15: 68. 1876. 
Rosa parviflora setigera Crépin, Bull. Soc. Bot. Belg. 15: 68. 1876. 
Rosa mexicana S. Wats. Proc. Am. Acad. 17: 354. 1882. Not R. mexicana Willd. 1825. 
Stem slender, terete, glabrous, 3-10 dm. high, bristly, especially the young shoots, armed 
with slender infrastipular prickles, which are straight, terete, 4-8 mm. long; stipules adnate, 
about 1 cm. long, narrow, glabrous or slightly pubescent, strongly glandular-ciliate on the 
margins and often glandular on the back; petioles and rachis glandular-hispid, otherwise 
glabrous or nearly so, the free portion of the petioles 3-10 mm. long; leaflets usually 5, rarely 
3 or 7, lance-elliptic or rarely oval, 1-4 cm. long, acute at both ends, light-green, glabrous or 
nearly so and somewhat shining above, often paler, glabrous or slightly pubescent on the 
veins and sometimes glandular beneath, sharply serrate with gland-tipped teeth, some of 
which are often denticulate or glandular-ciliate; flowers solitary; peduncles 1-3 cm. long, more 
or less glandular-hispid; hypanthium globose or slightly depressed, glandular-hispid, in fruit 
8-12 mm. broad; sepals lanceolate, glandular-hispid on the back, tomentose within, caudate- 
acuminate, 1.5-2.5 cm. long, some of them usually with lanceolate or subulate appendages, 
after anthesis reflexed and soon deciduous; petals rose-colored, 1.5—2.5 em. long; styles distinct, 
persistent, not exserted; achenes inserted in the bottom of the hypanthium. 
TYPE LOCALITY: Highlands and Catskills, New York. 
DISTRIBUTION: Massachusetts to Ontario, lowa, Texas, and Florida; Coahuila and Nuevo Le6én. 
Rosa Lyoni X serrulata. See under R. Lyoni. 
Rosa palustris < serrulata. See under R. palustris. 
Rosa serrulata X virginiana. See under R. virginiana. 
27. Rosa subserrulata Rydberg, sp. nov. 
Rosa serrulata Crépin, Bull. Soc. Bot. Belg. 15:91. 1876. Not R. serrulata Raf. 1820. 
Stem slender, 3—8 dm. high, terete, usually densely bristly and armed with slender infrastip- 
ular prickles, which are straight, diverging, 4-5 mm. long; flowering branches also very bristly 
and prickly, glandular-hispid; stipules adnate, about 1 cm. long, mostly narrow or the upper 
somewhat dilated, slightly pubescent or glabrous, glandular-ciliate, the free portion narrowly 
lanceolate; petiole and rachis more or less glandular-hispid and bristly; free portion of petioles 
3-5 cm. long; leaflets 3—7, lance-elliptic to oblanceolate or obovate, acute at both ends, light- 
green, thin, glabrous on both sides or pubescent on the veins beneath, sharply serrate with 
long lanceolate teeth, which are more or less gland-tipped and some of them often with one or 
two small teeth or glandular-ciliate; flowers solitary; pedicels 1-2 cm. long, glandular-hispid; 
hypanthium globose, more or less glandular-hispid, in fruit 8-10 mm. broad; sepals lanceolate, 
caudate-attenuate, about 1.5 cm. long, glandular-hispid without, tomentose within, entire 
or with a few subulate lobes, reflexed after anthesis and soon deciduous; petals rose-colored, 
about 2 cm. long, obcordate; styles distinct, persistent, not exserted; achenes in the bottom 
of the hypanthium. 
Type collected at Swan, Missouri, June 2, 1899, B. F. Bush 42 (herb. N. Y. Bot. Gard.). 
DISTRIBUTION: Missouri and Arkansas to Texas. 
28. Rosa Bicknellii Rydberg, sp. nov. 
Stem dark, 5-10 dm. tall, erect, branched, glabrous, terete, armed with rather stout, 
long prickles, which are 7-12 mm. long, flattened at the base, sometimes slightly curved, 
