ROSACE.E 399 



CONSPECTUS OF THE NATURAL GROUPS OF THE NORTH AMERICAN 

 ARBORESCENT SPECIES. 



1 . Nutlets without ventral cavities. 



*Veins of the leaves extending to the points of the lobes only. 



-*- Petioles short, usually slightly wing-margined above the middle, glandless or with 

 occasional minute glands; leaves cuneate at base. 



Corymbs compound, generally many-flowered; flowers appearing after the unfolding 



of the leaves; flesh of the fruit usually green or greenish yellow, dry and mealy. 



Leaves coriaceous or subcoriaceous, rarely thin, dark green and shining above, 



usually serrate only above the middle, their veins thin except on vigorous 



shoots; fruit mostly subglobose to short-oblong; nutlets 1-5, thick, usually 



obtuse and rounded at the ends, prominently ridged on the back. 



I. Crus-galli (page 400). 



Leaves membranaceous or subcoriaceous, mostly acute, their veins prominent; 

 fruit short-oblong to subglobose, often conspicuously punctate, '-!' long; 

 nutlets 2-5, prominently ridged on the back. II. Punctatae (page 422). 



Corymbs simple, few-flowered; flowers appearing with or before the unfolding of the 

 leaves; fruit scarlet, lustrous; flesh yellow, juicy, subacid; nutlets rounded and 

 slightly grooved on the back. III. ^Istivales (page 434). 



-^Petioles elongated, slender, eglandular or occasionally glandular; corymbs many- 

 flowered (few-flowered in one species each of Dilatatas and Intricatci). 

 +-I- Leaves acute or acuminate at the ends, broad at base on one species; fruit not 

 more than f ' in diameter; flesh usually thin and dry. IV. Virides (page 4S7). 

 M- Leaves usually broad at base. 



Fruit subglobose to short-oblong, often broader than high, red or green, often 

 slightly 5-angled, pruinose; mature calyx raised on a short tube; flesh of the 

 fruit dry and mealy ; nutlets 5, grooved on the back. V. Pruinosae (page 449) . 

 Fruit subglobose to short-oblong, ovoid or obovoid, generally longer than broad, 

 rarely slightly pruinose, mature calyx sessile; flesh of the fruit dry and mealy; 

 stamens 10, anthers rose color; leaves hairy above early in the season. 



VI. Silvicolae (page 453). 



Fruit short-oblong to obovoid, red or scarlet; flesh of the fruit usually soft and 

 juicy; anthers rose color or pink; leaves thin, at maturity glabrous below. 



VII. Tenuifoliae (page 456). 



Fruit subglobose, oblong or obovoid, crimson, scarlet, or rarely yellow; flesh thick, 

 occasionally succulent, and edible; nutlets usually 5, thin, pointed at the 

 ends, mostly obscurely grooved or ridged on the back; corymbs tomentose or 

 pubescent; leaves membranaceous to subcoriaceous, broad, rounded or cuneate 

 at base, at maturity usually pubescent or tomentose below. 



VIII. Molles (page 463). 



Fruit short-oblong to obovoid, scarlet; flesh usually soft and juicy; nutlets 3-5, 

 grooved and usually ridged on the back; corymbs glabrous or tomentose: 

 leaves thin or rarely subcoriaceous, oblong-ovate or oval, more or less acutely 

 lobed; anthers rose or purple; rarely w T hite in shrubby species. 



IX. Coccineae (page 488). 



Fruit subglobose to short-oblong, crimson, or red tinged with green, its calyx 

 enlarged and prominent; nutlets 5; stamens 20; anthers rose color; leaves 

 thin, at the end of vigorous shoots as broad or broader than long. 



X. Dilatatae (page 500). 

 n- Leaves cuneate at base. 



Corymbs many-flowered; leaves subcoriaceous; fruit subglobose, rarely short- 

 oblong; nutlets 2 or 3, obtuse at the ends, conspicuously ridged on the back; 

 corymbs glabrous or tomentose; leaves dark green and lustrous above. 



XI. Rotundifoliae (page 504). 



