240 TREES AND SHRUBS. 



nutlets four or five, broad and rounded at the ends, wider at the apex than at the base, ridged on the back with a broad high rounded 

 ridge, from 7 to 8 millimetres long and from 6 to 7 millimetres wide, the prominent hypostyle extending to below the middle of 

 the nutlet. 



A shrub, from 2 to 3 metres high, with small erect stems covered with smooth pale bark, spreading branches, and stout zigzag 

 branchlets dark red-brown when they first appear, chestnut-brown, very lustrous and marked by small pale lenticels at the end 

 of their first season and dull gray-brown the following year, and armed with stout chestnut-brown lustrous spines from 2 to 2.5 

 centimetres long. Flowers in the first week in May. Fruit ripens early in October. 



Missouri: low woods near small streams, in gravelly soil, Pleasant Grove, Ripley County, common, B. F. Bush, May 7, 1901 

 (No. 6, type, 6A, 6B, 6C, 6D, 6E, 6F, 6H), B. F. Bush and C. S. Sargent, October 4, 1912 (No. 6). 



Crataegus ambitiosa, n. sp. (Pruinosce.) 



Glabrous with the exception of the hairs on the young leaves. Leaves ovate to rhombic, acuminate, rounded or cuneate at the 

 base, finely doubly serrate with straight glandular teeth, and slightly divided into three or four pairs of small acute spreading 

 lateral lobes ; when they unfold covered above with soft white caducous hairs, nearly fully grown when the flowers open and then 

 very thin, yellow-green above, pale bluish green below, and at maturity thin, dark blue-green, smooth and lustrous on the upper 

 surface, paler blue-green on the lower surface, from 4 to 5 centimetres long and from 3 to 4 centimetres wide, with slender promi- 

 nent midribs, and thin primary veins extending to the points of the lobes ; petioles slender, slightly wing-margined at the apex, 

 glandular with minute often persistent glands, from 2 to 3.5 centimetres in length. Flowers 2 centimetres in diameter, on short 

 slender pedicels, in small compact mostly from five- to nine-flowered corymbs ; calyx-tube narrowly obconic, the lobes abruptly 

 narrowed from broad bases, acuminate, laciniately glandular-serrate usually only above the middle, reflexed after anthesis; stamens 

 twenty; anthers faintly tinged with pink in the bud, soon becoming yellow; styles four or five. Fruit on stout reddish drooping 

 pedicels, in few-fruited clusters, obovate, slightly narrowed and rounded at the apex, abruptly narrowed to the base, crimson, 

 more or less blotched with green, lustrous, marked by large pale dots, from 1.4 to 1.6 centimetres long, and from 1 to 1.2 centi- 

 metres in diameter; flesh thin, yellow-green, dry and mealy; nutlets four or five, thin, acute at the ends, irregularly ridged on 

 the back with a low grooved ridge, from 5.5 to 6 millimetres long and from 4 to 4.5 millimetres wide. 



An intricately branched shrub, from 4 to 5 metres high, with small stems covered with dark scaly bark, small ascending branches, 

 and very slender nearly straight branchlets, dark orange-green when they first appear, becoming light orange-brown, lustrous and 

 marked by small dark lenticels in their first season and dull grayish brown the following year, and armed with numerous very 

 slender straight or slightly curved chestnut-brown shining spines from 3.5 to 5 centimetres long. Flowers the end of May. Fruit 

 ripens early in October. 



Michigan : pastures in low moist ground on Lake Street, south of Read's Lake, east of Grand Rapids, Kent County, E. J. Cole, 

 May 15, 1901, May 30 and September 29, 1904 (No. 32, type), October 17, 1904 (No. 158). 



Crataegus comparata, n. sp. (Pruinosce.) 



Glabrous with the exception of a few deciduous hairs on the upper surface of the young leaves. Leaves oblong-ovate, acumi- 

 nate, broad and rounded or gradually narrowed and cuneate at the entire base, sharply doubly serrate above with straight glandu- 

 lar teeth, and slightly divided into four or five pairs of small lateral lobes ; nearly one-third grown when the flowers open and 

 then thin and yellow-green, and at maturity thick to subcoriaceous, dark bluish green, smooth and lustrous on the upper surface, 

 pale blue-green on the lower surface, from 6 to 8 centimetres long and from 4.5 to 6 centimetres wide, with thin midribs and 

 primary veins ; petioles slender, slightly wing-margined at the apex, rose-colored in the autumn, from 2.5 to 4 centimetres in 

 length ; leaves on vigorous shoots ovate, acuminate, rounded at the broad base, more coarsely serrate and more deeply lobed, from 

 } long and from 2.5 to 3 centimetres wide, with rose-colored midribs and primary veins. Flowers from 2 to 2.2 

 long slender pedicels, in narrow lax mostly seven- to ten-flowered corymbs ; calyx-tube narrowly 

 obconic, the lobes abruptly narrowed from the base, short, acuminate, glandular-serrate, reflexed after anthesis; stamens twenty; 

 anthers slightly tinged with pink ; styles four or five, surrounded at the base by a narrow ring of long pale hairs. Fruit on stout 

 drooping pedicels, obovate to oval, full and rounded at the ends, concave at the insertion of the pedicel, crimson, lustrous, from 1 

 to 1.2 centimetres long and from 9 to 10 millimetres in diameter ; calyx little enlarged, with a wide deep cavity, and small closely 

 appressed lobes dark red on the upper side below the middle ; flesh thin, yellow-green, dry and mealy; nutlets four or five, grad- 

 ually narrowed and rounded at the apex, acute at the base, rounded and grooved or irregularly ridged on the back, from 7 to 

 7.5 millimetres long and from 4 to 4.5 millimetres wide, the broad hypostyle extending to below the middle of the nutlet. 



An arborescent shrub, from 5 to 6 metres high, with stems 4 or 5 centimetres in diameter, covered with dark scaly bark, ascend- 

 ing and spreading branches forming a broad open head, and stout zigzag branchlets dark green tinged with red and marked by 

 pale lenticels when they first appear, light chestnut-brown and lustrous in their first season and dull gray-brown the following 

 year, and armed with stout nearly straight chestnut-brown shining spines from 4 to 6 centimetres long. Flowers the end of May. 

 Fruit ripens late in September or early in October. 



Michigan : Lake Street, south of Read's Lake, east of Grand Rapids, Kent County, E. J. Cole, May 10 and September 19, 1905 

 (No. 32-1 type). 



Crataegus tumida, n. sp. (Pruinosce.) 



Glabrous. Leaves oblong-ovate, acuminate, rounded, truncate, or slightly cordate at the base, coarsely doubly serrate with 

 straight spreading teeth, and usually slightly divided above the middle into short broad lobes; nearly fully grown when the flowers 

 open and then thin, light yellow-green, and at maturity thin, yellow-green and lustrous on the upper surface, pale bluish green on 

 and from 4.5 to 6.5 centimetres wide, with slender midribs, and thin primary veins 



